rutherford gold foil experiment ncert

• History & Society
• Science & Tech
• Biographies
• Animals & Nature
• Geography & Travel
• Arts & Culture
• Games & Quizzes
• On This Day
• One Good Fact
• New Articles
• Lifestyles & Social Issues
• Philosophy & Religion
• Politics, Law & Government
• World History
• Health & Medicine
• Browse Biographies
• Birds, Reptiles & Other Vertebrates
• Bugs, Mollusks & Other Invertebrates
• Environment
• Fossils & Geologic Time
• Entertainment & Pop Culture
• Sports & Recreation
• Visual Arts
• Demystified
• Image Galleries
• Infographics
• Top Questions
• Britannica Kids
• Saving Earth
• Space Next 50
• Student Center

What is the model of the atom proposed by Ernest Rutherford?

What is the rutherford gold-foil experiment, what were the results of rutherford's experiment, what did ernest rutherford's atomic model get right and wrong, what was the impact of ernest rutherford's theory.

Rutherford model

Our editors will review what you’ve submitted and determine whether to revise the article.

• UC Davis - The Rutherford Scattering Experiment
• Chemistry LibreTexts - Rutherford's Experiment- The Nuclear Model of the Atom

The atom , as described by Ernest Rutherford , has a tiny, massive core called the nucleus . The nucleus has a positive charge. Electrons are particles with a negative charge. Electrons orbit the nucleus. The empty space between the nucleus and the electrons takes up most of the volume of the atom.

A piece of gold foil was hit with alpha particles , which have a positive charge. Most alpha particles went right through. This showed that the gold atoms were mostly empty space. Some particles had their paths bent at large angles. A few even bounced backward. The only way this would happen was if the atom had a small, heavy region of positive charge inside it.

The previous model of the atom, the Thomson atomic model , or the “plum pudding” model, in which negatively charged electrons were like the plums in the atom’s positively charged pudding, was disproved. The Rutherford atomic model relied on classical physics. The Bohr atomic model , relying on quantum mechanics, built upon the Rutherford model to explain the orbits of electrons.

The Rutherford atomic model was correct in that the atom is mostly empty space. Most of the mass is in the nucleus, and the nucleus is positively charged. Far from the nucleus are the negatively charged electrons. But the Rutherford atomic model used classical physics and not quantum mechanics. This meant that an electron circling the nucleus would give off electromagnetic radiation . The electron would lose energy and fall into the nucleus. In the Bohr model, which used quantum theory, the electrons exist only in specific orbits and can move between these orbits.​

The gold-foil experiment showed that the atom consists of a small, massive, positively charged nucleus with the negatively charged electrons being at a great distance from the centre. Niels Bohr built upon Rutherford’s model to make his own. In Bohr’s model the orbits of the electrons were explained by quantum mechanics.

Rutherford model , description of the structure of atoms proposed (1911) by the New Zealand-born physicist Ernest Rutherford . The model described the atom as a tiny, dense, positively charged core called a nucleus, in which nearly all the mass is concentrated, around which the light, negative constituents , called electrons , circulate at some distance, much like planets revolving around the Sun .

The nucleus was postulated as small and dense to account for the scattering of alpha particles from thin gold foil, as observed in a series of experiments performed by undergraduate Ernest Marsden under the direction of Rutherford and German physicist Hans Geiger in 1909. A radioactive source emitting alpha particles (i.e., positively charged particles, identical to the helium atom nucleus and 7,000 times more massive than electrons) was enclosed within a protective lead shield. The radiation was focused into a narrow beam after passing through a slit in a lead screen. A thin section of gold foil was placed in front of the slit, and a screen coated with zinc sulfide to render it fluorescent served as a counter to detect alpha particles. As each alpha particle struck the fluorescent screen , it produced a burst of light called a scintillation, which was visible through a viewing microscope attached to the back of the screen. The screen itself was movable, allowing Rutherford and his associates to determine whether or not any alpha particles were being deflected by the gold foil.

Most alpha particles passed straight through the gold foil, which implied that atoms are mostly composed of open space. Some alpha particles were deflected slightly, suggesting interactions with other positively charged particles within the atom. Still other alpha particles were scattered at large angles, while a very few even bounced back toward the source. (Rutherford famously said later, “It was almost as incredible as if you fired a 15-inch shell at a piece of tissue paper and it came back and hit you.”) Only a positively charged and relatively heavy target particle, such as the proposed nucleus, could account for such strong repulsion. The negative electrons that balanced electrically the positive nuclear charge were regarded as traveling in circular orbits about the nucleus. The electrostatic force of attraction between electrons and nucleus was likened to the gravitational force of attraction between the revolving planets and the Sun. Most of this planetary atom was open space and offered no resistance to the passage of the alpha particles.

The Rutherford model supplanted the “plum-pudding” atomic model of English physicist Sir J.J. Thomson , in which the electrons were embedded in a positively charged atom like plums in a pudding. Based wholly on classical physics , the Rutherford model itself was superseded in a few years by the Bohr atomic model , which incorporated some early quantum theory . See also atomic model .

• Class 6 Maths
• Class 6 Science
• Class 6 Social Science
• Class 6 English
• Class 7 Maths
• Class 7 Science
• Class 7 Social Science
• Class 7 English
• Class 8 Maths
• Class 8 Science
• Class 8 Social Science
• Class 8 English
• Class 9 Maths
• Class 9 Science
• Class 9 Social Science
• Class 9 English
• Class 10 Maths
• Class 10 Science
• Class 10 Social Science
• Class 10 English
• Class 11 Maths
• Class 11 Computer Science (Python)
• Class 11 English
• Class 12 Maths
• Class 12 English
• Class 12 Economics
• Class 12 Accountancy
• Class 12 Physics
• Class 12 Chemistry
• Class 12 Biology
• Class 12 Computer Science (Python)
• Class 12 Physical Education
• GST and Accounting Course
• Excel Course
• Tally Course
• Finance and CMA Data Course
• Payroll Course

Interesting

• Learn English
• Learn Excel
• Learn Tally
• Learn GST (Goods and Services Tax)
• Learn Accounting and Finance
• GST Tax Invoice Format
• Accounts Tax Practical
• Tally Ledger List
• GSTR 2A - JSON to Excel

Are you in school ? Do you love Teachoo?

We would love to talk to you! Please fill this form so that we can contact you

• NCERT Questions
• Questions from Inside the chapter
• Teachoo Questions

Rutherford Atomic Model

Last updated at April 16, 2024 by Teachoo

As per Rutherford Nuclear Model of Atom ,

• Every atom has a nucleus .
• The size of the nucleus is very small . It is 1/10 the size of an atom .
• This nucleus is positively charged .
• Even though the nucleus is of small size, it has a very high mass . Nearly all the mass of an atom is inside the nucleus.
• Electrons revolve around the nucleus in a circular path .

How was the Rutherford Model formed?

• It was formed by the scientist Ernest Rutherford .

He designed the model after performing Alpha Particle Scattering Experiment on a gold foil .

What is an alpha particle?

• Alpha particles are nucleus of helium atoms . It has a charge of +2 . The fast moving alpha particles have a good amount of energy.
• The mass of an alpha - particle is 4u .

Why did Rutherford use a gold foil?

• He selected a gold foil because he wanted as thin a layer as possible . This gold foil was about 1000 atoms thick .

What did Rutherford expect before the experiment?

• Mass of the alpha particles was 4u while that of the proton is 1u. Hence, they were much heavier than the proton.
• Rutherford expected that alpha particles would deflect a little by the subatomic particles (protons and electrons) in the gold atoms.
• But since alpha particles were much heavier than protons , he did not expect to see large deflections.

What was Rutherford's Alpha Particle Scattering Experiment?

• In this experiment, Rutherford made fast moving alpha particles to fall on a gold foil .
• He observed that:
• Many of fast moving alpha particles pass straight through the gold foil with no deflection at all
• Some of the alpha particles were deflected by foil at small angles.
• Very less alpha particles(1 out of every 12000) were reflected back  at 180 degree (rebound)

Rutherford’s observations from his experiment: -

• Most of spaces inside atom was empty This is because most of the fast moving alpha particles pass straight through the gold foil.
• Positive charge of atom occupies very little space This is because only some of the alpha particles were deflected by the foil at small angles.
• All mass of atom and positive charged was concentrated in very small volume of atom called Nucleus This is because very less alpha particles were reflected back at 180 degree (rebound).

Note: From his experiment, he estimated that, radius of an atom is about 10 5   more than the radius of a nucleus.

What was Rutherford's model of an atom?

Rutherford's model of an atom stated that:

• There is a positively charged centre in an atom called the nucleus . Nearly all the mass of an atom resides in the nucleus .
• The electrons (negatively charged particles) revolve around the nucleus in circular paths.
• The size of the nucleus is very small as compared to the size of the atom .

Maninder Singh

CA Maninder Singh is a Chartered Accountant for the past 14 years and a teacher from the past 18 years. He teaches Science, Economics, Accounting and English at Teachoo

Hi, it looks like you're using AdBlock :(

Please login to view more pages. it's free :), solve all your doubts with teachoo black.

• Skip to main content
• Skip to secondary menu
• Skip to primary sidebar

Class Notes

Free Class Notes & Study Material

Rutherford Model of an Atom

Last Updated on July 3, 2023 By Mrs Shilpi Nagpal

Question 1 Name the particle used by Rutherford in his experiment to determine the structure of an atom?

Question 2 Explain the Rutherford’s scattering experiment?

Question 3 What observation were made by Rutherford’s in his experiment?

Question 4 Give the postulates of Rutherford’s model of an atom?

Question 5 State one drawback of Rutherford’s model of an atom?

• 1 Alpha Particles
• 2 Rutherford Model of an atom
• 3 Drawback of Rutherford Model of an Atom

Alpha Particles

Alpha particles is a positively charged particle having 2 units of positive charge and 4 units of mass. They are emitted from radioactive elements like Radium and Polonium . The fast moving alpha particles have considerable amount of energy. They can penetrate through the matter.

Experimental set Up

(1) He selected a thin gold foil.

(2) The fast moving alpha particles are allowed to strike a very thin gold foil in vacuum.

Observation

(1) Most of the alpha particles pass straight through the gold foil without any deflection from their original path.

(2) A few alpha particles are deflected through small angles and few are deflected through large angles.

(3) A very few alpha particles completely rebound on hitting the gold foil and turn back on their path.

Conclusion (1) As most of the alpha particles pass straight through the gold foil without any deflection, it shows that there is lot of empty space in an atom.

(2) Some of the alpha particles are deflected through small and large angles shows that there is positive centre in the atom which repel the positively charged alpha particles.

(3) Very few alpha particles completely rebound on hitting shows that all positive charge and mass of the atom were concentrated in very small volume with the atom.

Rutherford Model of an atom

(1) An atom consist of positively charged, dense and very small nucleus containing protons and neutrons.The entire mass of an atom is concentrated in the nucleus.

(2) The nucleus is surrounded by negatively charged electrons. The electrons are revolving around the nucleus in circular paths at very high speed.These circular paths of the electrons are called orbits.

(3) An atom is electrically neutral because the number of protons and electrons is equal.

(4) The size of nucleus is very small as compared to size of atom.

Drawback of Rutherford Model of an Atom

He does not explain the stability of an atom.In the Rutherford’s model of an atom, the negatively charged electron revolves around the positively charged nucleus in circular path. If an object moves in a circular path, the its motion is said to be accelerated. This means that motion of an electron revolving around the nucleus is accelerated. If a charged particle undergoes accelerated motion, then it must radiate energy continuously. Thus the energy of revolving electron will decrease gradually and their speed will also go on decreasing and ultimately the electrons should fall into the nucleus. This makes atom very unstable and hence the atom should collapse.

About Mrs Shilpi Nagpal

Author of this website, Mrs. Shilpi Nagpal is MSc (Hons, Chemistry) and BSc (Hons, Chemistry) from Delhi University, B.Ed. (I. P. University) and has many years of experience in teaching. She has started this educational website with the mindset of spreading free education to everyone.

Reader Interactions

October 21, 2018 at 3:44 am

Thanks for the information you always give GOD BLESS

November 14, 2018 at 8:43 pm

November 30, 2018 at 6:56 pm

December 19, 2018 at 8:42 pm

thank you so much for the explaination. It was so difficult for me to understand the rutherford gold foil experiment. but u made it so easy to understand this concept.thank u sooo much.

February 26, 2019 at 7:28 am

Thanks for this explanation

March 2, 2019 at 7:07 pm

Thank u so much

August 1, 2019 at 3:48 pm

The picture of the atomic model you show at “Conclusion” after point 4) is actually Bohr’s model of the atom (since it has electrons on discrete energy levels). As you said, the electron orbiting around the nucleus would constantly lose energy so it would collapse into the nucleus eventually (Rutherford 1911). It was 1913 when Rutherford together with Bohr figured out that the electron can have stable orbits around the nucleus ONLY at certain “distances”, and nowhere else. However, an electron can jump between these stable orbits (also known as discrete energy levels – as you show in that picture). When the electron jumps “down” (i.e. closer to the nucleus) the process is called “de-excitation”, and it is usually accompanied by the emission of a photon (light). This model could finally explain the “Balmer series”, a.k.a. the emission spectrum of hydrogen.

August 1, 2019 at 10:08 pm

We have made the changes as per your suggestions. Thank you so much for reading our website content so carefully and advising.

Keep Reading !!

September 7, 2019 at 5:05 am

Thanks for giving me a simple explanation

February 12, 2020 at 7:33 pm

Thanks a lot for the information because of this I got very good mark in project making this what the best

January 7, 2022 at 10:23 am

Thanks a lot for the diagrams they helped me a lot .

February 13, 2022 at 8:57 pm

Thank for this kind of help

February 7, 2023 at 7:24 am

Thanks for simple explanation It helps me more in my viva.

February 4, 2024 at 5:38 am

Nice brief about the rutherford model Thanku

Leave a Reply

Your email address will not be published. Required fields are marked *

• Why Does Water Expand When It Freezes

Gold Foil Experiment

• Faraday Cage
• Oil Drop Experiment
• Magnetic Monopole
• Why Do Fireflies Light Up
• Types of Blood Cells With Their Structure, and Functions
• The Main Parts of a Plant With Their Functions
• Parts of a Flower With Their Structure and Functions
• Parts of a Leaf With Their Structure and Functions
• Why Does Ice Float on Water
• Why Does Oil Float on Water
• How Do Clouds Form
• What Causes Lightning
• How are Diamonds Made
• Types of Meteorites
• Types of Volcanoes
• Types of Rocks

Who did the Gold Foil Experiment?

The gold foil experiment was a pathbreaking work conducted by scientists Hans Geiger and Ernest Marsden under the supervision of Nobel laureate physicist Ernest Rutherford that led to the discovery of the proper structure of an atom . Known as the Geiger-Marsden experiment, it was performed at the Physical Laboratories of the University of Manchester between 1908 and 1913.

The prevalent atomic theory at the time of the research was the plum pudding model that was developed by Lord Kelvin and further improved by J.J. Thomson. According to the theory, an atom was a positively charged sphere with the electrons embedded in it like plums in a Christmas pudding.

With neutrons and protons yet to be discovered, the theory was derived following the classical Newtonian Physics. However, in the absence of experimental proof, this approach lacked proper acceptance by the scientific community.

What is the Gold Foil Experiment?

Description.

The method used by scientists included the following experimental steps and procedure. They bombarded a thin gold foil of thickness approximately 8.6 x 10 -6 cm with a beam of alpha particles in a vacuum. Alpha particles are positively charged particles with a mass of about four times that of a hydrogen atom and are found in radioactive natural substances. They used gold since it is highly malleable, producing sheets that can be only a few atoms thick, thereby ensuring smooth passage of the alpha particles. A circular screen coated with zinc sulfide surrounded the foil. Since the positively charged alpha particles possess mass and move very fast, it was hypothesized that they would penetrate the thin gold foil and land themselves on the screen, producing fluorescence in the part they struck.

Like the plum pudding model, since the positive charge of atoms was evenly distributed and too small as compared to that of the alpha particles, the deflection of the particulate matter was predicted to be less than a small fraction of a degree.

Observation

Though most of the alpha particles behaved as expected, there was a noticeable fraction of particles that got scattered by angles greater than 90 degrees. There were about 1 in every 2000 particles that got scattered by a full 180 degree, i.e., they retraced their path after hitting the gold foil.

Simulation of Rutherford’s Gold Foil Experiment Courtesy: University of Colorado Boulder

The unexpected outcome could have only one explanation – a highly concentrated positive charge at the center of an atom that caused an electrostatic repulsion of the particles strong enough to bounce them back to their source. The particles that got deflected by huge angles passed close to the said concentrated mass. Most of the particles moved undeviated as there was no obstruction to their path, proving that the majority of an atom is empty.

In addition to the above, Rutherford concluded that since the central core could deflect the dense alpha particles, it shows that almost the entire mass of the atom is concentrated there. Rutherford named it the “nucleus” after experimenting with various gases. He also used materials other than gold for the foil, though the gold foil version gained the most popularity.

He further went on to reject the plum pudding model and developed a new atomic structure called the planetary model. In this model, a vastly empty atom holds a tiny nucleus at the center surrounded by a cloud of electrons. As a result of his gold foil experiment, Rutherford’s atomic theory holds good even today.

Rutherford’s Atomic Model

Rutherford’s Gold Foil Experiment Animation

• Rutherford demonstrated his experiment on bombarding thin gold foil with alpha particles contributed immensely to the atomic theory by proposing his nuclear atomic model.
• The nuclear model of the atom consists of a small and dense positively charged interior surrounded by a cloud of electrons.
• The significance and purpose of the gold foil experiment are still prevalent today. The discovery of the nucleus paved the way for further research, unraveling a list of unknown fundamental particles.
• Chemed.chem.purdue.edu
• Chem.libretexts.org
• Large.stanford.edu
• Radioa ctivity.eu.com

Article was last reviewed on Friday, February 3, 2023

Related articles

5 responses to “Gold Foil Experiment”

Super very much helpful to me,clear explanation about every act done by our Rutherford that is under different sub headings ,which is very much clear to ,to study .very much thanks to the science facts.com.thank u so much.

Good explanation,very helpful ,thank u ,so much

very clear and helpful, perfect for my science project!

Thank you for sharing the interactive program on the effects of the type of atom on the experiment! Looking forward to sharing this with my ninth graders!

Rutherford spearheaded with a team of scientist in his experiment of gold foil to capture the particles of the year 1911. It’s the beginning of explaining particles that float and are compacted . Rutherford discovered this atom through countless experiments which was the revolutionary discovery of the atomic nuclear . Rutherford name the atom as a positive charge and the the center is the nucleus.

Barack Hussein Obama

Mrs. Danize Obama

Leave a Reply Cancel reply

Your email address will not be published. Required fields are marked *

Save my name, email, and website in this browser for the next time I comment.

Popular Articles

Join our Newsletter

Fill your E-mail Address

Related Worksheets

• Privacy Policy

© 2024 ( Science Facts ). All rights reserved. Reproduction in whole or in part without permission is prohibited.

• Sign in / Register
• Administration
• Edit profile

The PhET website does not support your browser. We recommend using the latest version of Chrome, Firefox, Safari, or Edge.

Experimental Evidence for the Structure of the Atom

George sivulka march 23, 2017, submitted as coursework for ph241 , stanford university, winter 2017, introduction.

The Rutherford Gold Foil Experiment offered the first experimental evidence that led to the discovery of the nucleus of the atom as a small, dense, and positively charged atomic core. Also known as the Geiger-Marsden Experiments, the discovery actually involved a series of experiments performed by Hans Geiger and Ernest Marsden under Ernest Rutherford. With Geiger and Marsden's experimental evidence, Rutherford deduced a model of the atom, discovering the atomic nucleus. His "Rutherford Model", outlining a tiny positively charged atomic center surrounded by orbiting electrons, was a pivotal scientific discovery revealing the structure of the atoms that comprise all the matter in the universe.

The experimental evidence behind the discovery involved the scattering of a particle beam after passing through a thin gold foil obstruction. The particles used for the experiment - alpha particles - are positive, dense, and can be emitted by a radioactive source. Ernest Rutherford discovered the alpha particle as a positive radioactive emission in 1899, and deduced its charge and mass properties in 1913 by analyzing the charge it induced in the air around it. [1] As these alpha particles have a significant positive charge, any significant potential interference would have to be caused by a large concentration of electrostatic force somewhere in the structure of the atom. [2]

Previous Model of the Atom

The scattering of an alpha particle beam should have been impossible according to the accepted model of the atom at the time. This model, outlined by Lord Kelvin and expanded upon by J. J. Thompson following his discovery of the electron, held that atoms were comprised of a sphere of positive electric charge dotted by the presence of negatively charged electrons. [3] Describing an atomic model similar to "plum pudding," it was assumed that electrons were distributed throughout this positive charge field, like plums distributed in the dessert. However, this plum pudding model lacked the presence of any significant concentration of electromagnetic force that could tangibly affect any alpha particles passing through atoms. As such, alpha particles should show no signs of scattering when passing through thin matter. [4] (see Fig. 2)

The Geiger Marsden Experiments

Testing this accepted theory, Hans Geiger and Ernest Marsden discovered that atoms indeed scattered alpha particles, a experimental result completely contrary to Thompson's model of the atom. In 1908, the first paper of the series of experiments was published, outlining the apparatus used to determine this scattering and the scattering results at small angles. Geiger constructed a two meter long glass tube, capped off on one end by radium source of alpha particles and on the other end by a phosphorescent screen that emitted light when hit by a particle. (see Fig. 3) Alpha particles traveled down the length of the tube, through a slit in the middle and hit the screen detector, producing scintillations of light that marked their point of incidence. Geiger noted that "in a good vacuum, hardly and scintillations were observed outside of the geometric image of the slit, "while when the slit was covered by gold leaf, the area of the observed scintillations was much broader and "the difference in distribution could be noted with the naked eye." [5]

On Rutherford's request, Geiger and Marsden continued to test for scattering at larger angles and under different experimental parameters, collecting the data that enabled Rutherford to further his own conclusions about the nature of the nucleus. By 1909, Geiger and Marsden showed the reflection of alpha particles at angles greater than 90 degrees by angling the alpha particle source towards a foil sheet reflector that then would theoretically reflect incident particles at the detection screen. Separating the particle source and the detector screen by a lead barrier to reduce stray emission, they noted that 1 in every 8000 alpha particles indeed reflected at the obtuse angles required by the reflection of metal sheet and onto the screen on the other side. [6] Moreover, in 1910, Geiger improved the design of his first vacuum tube experiment, making it easier to measure deflection distance, vary foil types and thicknesses, and adjust the alpha particle stream' velocity with mica and aluminum obstructions. Here he discovered that both thicker foil and foils made of elements of increased atomic weight resulted in an increased most probable scattering angle. Additionally, he confirmed that the probability for an angle of reflection greater than 90 degrees was "vanishingly small" and noted that increased particle velocity decreased the most probably scattering angle. [7]

Rutherford's Atom

Backed by this experimental evidence, Rutherford outlined his model of the atom's structure, reasoning that as atoms clearly scattered incident alpha particles, the structure contained a much larger electrostatic force than earlier anticipated; as large angle scattering was a rare occurrence, the electrostatic charge source was only contained within a fraction of the total volume of the atom. As he concludes this reasoning with the "simplest explanation" in his 1911 paper, the "atom contains a central charge distributed through a very small volume" and "the large single deflexions are due to the central charge as a whole." In fact, he mathematically modeled the scattering patterns predicted by this model with this small central "nucleus" to be a point charge. Geiger and Marsden later experimentally verified each of the relationships predicted in Rutherford's mathematical model with techniques and scattering apparatuses that improved upon their prior work, confirming Rutherford's atomic structure. [4, 8, 9] (see Fig. 1)

With the experimentally analyzed nature of deflection of alpha rays by thin gold foil, the truth outlining the structure of the atom falls into place. Though later slightly corrected by Quantum Mechanics effects, the understanding of the structure of the the atom today almost entirely follows form Rutherford's conclusions on the Geiger and Marsden experiments. This landmark discovery fundamentally furthered all fields of science, forever changing mankind's understanding of the world around us.

© George Sivulka. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.

[1] E. Rutherford, "Uranium Radiation and the Electrical Conduction Produced By It," Philos. Mag. 47 , 109 (1899).

[2] E. Rutherford, "The Structure of the Atom," Philos. Mag. 27 , 488 (1914).

[3] J. J. Thomson, "On the Structure of the Atom: an Investigation of the Stability and Periods of Oscillation of a Number of Corpuscles Arranged at Equal Intervals Around the Circumference of a Circle; with Application of the Results to the Theory of Atomic Structure," Philos. Mag. 7 , 237 (1904).

[4] E. Rutherford, "The Scattering of α and β Particles by Matter and the Structure of the Atom," Philos. Mag. 21 , 669 (1911).

[5] H. Geiger, "On the Scattering of the α Particles by Matter," Proc. R. Soc. A 81 , 174 (1908).

[6] H. Geiger and E. Marsden, "On a Diffuse Reflection of the α-Particles," Proc. R. Soc. A 82 , 495 (1909).

[7] H. Geiger, "The Scattering of the α Particles by Matter," Proc. R. Soc. A 83 , 492 (1910).

[8] E. Rutherford, "The Origin of α and β Rays From Radioactive Substances," Philos. Mag. 24 , 453 (1912).

[9] H. Geiger and E. Marsden, "The Laws of Deflexion of α Particles Through Large Angles," Philos. Mag. 25 , 604 (1913).

NCERT Exemplar Chapter 4 Structure of the Atom Class 9 Science Solutions

Ncert exemplar class 9 science chapter 4 structure of the atom solutions.

NCERT Exemplar Solutions for Class 9 Science Chapter 4 Structure of the Atom covers all the important questions and answers as well as advanced level questions. It helps in learning about the Charged Particles of Matter, where does this charge come from, Structure of an Atom, different models of atoms proposed, Thomson’s Model of an Atom, Rutherford’s Models of an Atom, nucleus of an atom, orbits and Bohr’s Model of an Atom.

The  NCERT Exemplar solutions for class 9 science  is very important in the examination. NCERT  Exemplar Solutions for Class 9 Science Chapter 4 Structure of the Atom  is provided by our experts. They prepared the best solutions which help the students in understanding the solutions in an easy way. This chapters also covers the other topics like neutrons, proton, electron of an atom, isotopes, isobars, how are the electrons distributed in different shells, valence electrons, atomic number and mass number.

NCERT Exemplar Solutions for Chapter 4 Structure of the Atom Class 9 Science

Multiple choice questions.

1. Which of the following correctly represent the electronic distribution in the Mg atom? (a) 3, 8, 1 (b) 2, 8, 2 (c) 1, 8, 3 (d) 8, 2, 2

(b) 2, 8, 2

Atomic number of Mg is 12.Therefore the electronic distribution will be 1s 2 2s 2 2p 6 3s 2 .

2. Rutherford’s ‘alpha (a ) particles scattering experiment’ resulted in to discovery of : (a) Electron (b) Proton (c) Nucleus in the atom (d) Atomic mass

(c) Nucleus in the atom

Rutherford’s ‘alpha (α) particles scattering experiment’ showed that few alpha particles returned to their original path. This showed the presence of nucleus in the centre.

3. The number of electrons in an element X is 15 and the number of neutrons is 16. Which of the following is the correct representation of the element? (a)  15 X 31 (b)  16 X 31 (c)  15 X 16 (d)  16 X 15

(a)  15 X 31

Atomic number is the number of protons in an element. Number of protons and electrons are equal in an element. The atomic number is written as a subscript and the mass number is written as the superscript of the element.

4. Dalton’s atomic theory successfully explained : (i) Law of conservation of mass (ii) Law of constant composition (iii) Law of radioactivity (iv) Law of multiple proportions (a) (i), (ii) and (iii) (b) (i), (iii) and (iv) (c) (ii), (iii) and (iv) (d) (i), (ii) and (iv)

(d) (i), (ii) and (iv)

Dalton’s theory explains the Law of conservation of mass, Law of constant composition, Law of multiple proportion.

5. Which of the following statements about Rutherford’s model of atom are correct? (i) considered the nucleus as positively charged (ii) established that the a-particles are four times heavy as a hydrogen atom (iii) can be compared to solar system (iv) was in agreement with Thomson’s model (a) (i) and (iii) (b) (ii) and (iii) (c) (i) and (iv) (d) Only (i)

(a) (i) and (iii)

The positively charged alpha particles were deflected by the nucleus. This indicates that the nucleus is positively charged. Rutherford also postulated that electrons are arranged in an atom around the nucleus like planets arranged around sun.

6. Which of the following are true for an element? (i) Atomic number = number of protons + number of electrons (ii) Mass number = number of protons + number of neutrons (iii) Atomic mass = number of protons = number of neutrons (iv) Atomic number = number of protons = number of electrons (a) (i) and (ii) (b) (i) and (iii) (c) and (iii) (d) (ii) and (iv)

(d) (ii) and (iv)

Atomic number Z is the number of proton present in an atom. This is also equal to number of electrons in an atom. As the mass of neutron is negligible, number of protons and electron are added to obtain mass number of an element.

7. In the Thomson’s model of atom, which of the following statements are correct? (i) The mass of the atom is assumed to be uniformly distributed over the atom. (ii) The positive charge is assumed to be uniformly distributed over the atom. (iii) The electrons are uniformly distributed in the positively charged sphere. (iv) The electrons attract each other to stabilise the atom. (a) (i), (ii) and (iii) (b) (i) and (iii) (c) (i) and (iv) (d) (i), (iii) and (iv)

(a) (i), (ii) and (iii)

Thomson proposed that negatively charged electron are stabilised by positively charged protons in the nucleus.

8. Rutherford’s a -particle scattering experiment showed that : (i) Electrons have negative charge. (ii) The mass and positive charge of the atom is concentrated in the nucleus. (iii) Neutron exists in the nucleus. (iv) Most of the space in atom is empty. Which of the above statements are correct? (a) (i) and (iii) (b) (ii) and (iv) (c) (i) and (iv) (d) (iii) and (iv)

(b) (ii) and (iv)

9. The ion of an element has 3 positive charges. Mass number of the atom is 27 and the number of neutrons is 14. What is the number of electrons in the ion? (a) 13 (b) 10 (c) 14 (d) 16

Mass number (A) of the atom = 27 Number of neutron in the atom =14 Number of electrons = Mass number - Number of neutrons = 27-14 = 13 Since ions of the element has 3 positive charges number of electron in the ion is 13-3 which equal 10.

10. Identify the  Mg 2+  ion from the fig. where, n and p represent the number of neutrons and protons respectively :

11. In a sample of ethyl ethanoate (CH 3 COOC 2 H 5 ), the two oxygen atoms have the same number of electrons but different number of neutrons. Which of the following is the correct reason for it? (a) One of the oxygen atoms has gained electrons. (b) One of the oxygen atoms has gained two neutrons. (c) The two oxygen atoms are isotopes. (d) The two oxygen atoms are isobars.

(c) The two oxygen atoms are isotopes.

Two oxygen atoms in CH 3 COOC 2 H 5 can have different number of neutrons only if the two O-atoms are isotopes. Isotopes of an element have same number of protons (and electrons) but different number of neutrons.

12. Elements with valency 1 are : (a) Always metals (b) Always metalloids (c) Either metals or non-metals (d) Always non-metals

(c) Either metals or non-metals

If an element shows positive valency then it is a metal and if it shows negative valency then it is a non-metal.

13. The first model of an atom was given by : (a) N. Bohr (b) E. Goldstein (c) Rutherford (d) J.J. Thomson

(d) J.J. Thomson

14. An atom with 3 protons and 4 neutrons will have a valency of : (a) 3 (b) 7 (c) 1 (d) 4

15. The electron distribution in an aluminium atom is : (a) 2, 8, 3 (b) 2, 8, 2 (c) 8, 2, 3 (d) 2, 3, 8

(a) 2, 8, 3

Atomic number of Aluminium is 13. Therefore, the first shell can have maximum of 2 electrons and the second shell holds a maximum of 8 electrons.

16. Which of the following fig. do not represent Bohr’s model of an atom correctly?

(a) (i) and (ii) (b) (ii) and (iii) (c) (ii) and (iv) (d) (i) and (iv)

(c) (ii) and (iv)

First shell can have a maximum of 2 electrons and the second shell can have a maximum of 8 electrons.

17. Which of the following statement is always correct? (a) An atom has equal number of electrons and protons. (b) An atom has equal number of electrons and neutrons. (c) An atom has equal number of protons and neutrons. (d) An atom has equal number of electrons, protons and neutrons.

(a) An atom has equal number of electrons and protons.

In an atom the number of protons is always equal to number of electrons.

18. Atomic models have been improved over the years. Arrange the following atomic models in the order of their chronological order :

(i) Rutherford’s atomic model,

(ii) Thomson’s atomic model,

(iii) Bohr’s atomic model. (a) (i), (ii) and (iii) (b) (ii), (iii) and (i) (c) (ii), (i) and (iii) (d) (iii), (ii) and (i)

(c) (ii), (i) and (iii)

Short Answer Questions

19. Is it possible for the atom of an element to have one electron, one proton and no neutron? If so, name the element.

Yes, Hydrogen is the element which has only 1 proton and 1 electron and no neutron. Therefore there is no repulsive force in the nucleus and hence it is stable. 1 proton means atomic no. (Z) = 1 1 neutron means mass no. (A) = p + n = 1 + 1 = 2 1 electron and 1 proton mean that atom is electrically neutral. Hence, the element is  1 1 H (An isotop of Hydrogen – Deuterium)

20. Write any two observations which support the fact that atoms are divisible.

• Discovery of electrons and protons support the fact that atoms are divisible.
• During a chemical reaction, there is either transfer or sharing of electrons which leads to the rearrangement of electrons in the atom.

21. Will  35 Cl and  37 Cl have different valencies? Justify your answer.

No,  35 Cl and  37 Cl both are the isotopes of the same element hence they cannot have different valencies. Both atoms have valency 1.

22. Why did Rutherford select a gold foil in his a-ray scattering experiment?

Gold is the most malleable metal and Rutherford wanted the thinnest layer. Therefore, Rutherford used gold for his scattering experiment as it is a heavy metal with high atomic number and it is highly malleable.

23. Find out the valency of the atoms represented by the fig. (a) and (b).

As atom (a) has 8 electron in its valence shell, it has zero valency.

Atom (b) has a valency of +1 as it has 7 electrons in it outermost shell. To achieve the octet configuration, atom (b) will accept 1 electron.

24. One electron is present in the outermost shell of the atom of an element X. What would be the nature and value of charge on the ion formed if this electron is removed from the outermost shell?

A cation is formed if an electron is removed from the outermost shell and the charge of the element will be +1.

25. Write down the electron distribution of chlorine atom. How many electrons are there in the L shell? (Atomic number of chlorine is 17.)

Atomic number of chlorine atom = 17

So, its electronic configuration is 17 Cl = K-2, L-8, M-7

26. In the atom of an element X, 6 electrons are present in the outermost shell. If it acquires noble gas configuration by accepting requisite number of electrons, then what would be the charge on the ion so formed?

6 electrons are already present in the outermost orbital. In order to attain noble gas configuration the element has to accept two electrons. Therefore, the charge on an atom of element X is -2.

27. What information do you get from the fig. about the atomic number, mass number and valency of atoms X, Y and Z? Give your answer in a tabular form.

28. In response to a question, a student stated that in an atom, the number of protons is greater than the number of neutrons, which in turn is greater than the number of electrons. Do you agree with the statement? Justify your answer.

The statement is incorrect. In a neutral atom the number of protons and electrons is always equal. Number of neutron can be greater than the number of electron. Number of neutron can be equal to or greater than the number of protons because mass number is equal to double the atomic number.

29. Calculate the number of neutrons present in the nucleus of an element X which is represented as  15 31 X.

Mass number = No. of protons + No. of neutrons = 31 ∴ Number of neutrons = 31–number of protons = 31–15 = 16

30. Match the names of the scientists given in column A with their contributions towards the understanding of the atomic structure as given in column B :

31. The atomic number of calcium and argon are 20 and 18 respectively, but the mass number of both these elements is 40. What is the name given to such a pair of elements?

Isobars are elements with different atomic numbers but same mass numbers. Calcium and argon are isobars.

32. Complete the table on the basis of information available in the symbols given below : (a)  17 Cl 35  (b)  6 C 12  (c)  35 Br 85

33. Helium atom has 2 electrons in its valence shell but its valency is not 2. Explain.

As Helium atom has 2 electrons in its outermost shell, its duplet is complete. Therefore the valency is zero.

34. Fill in the blanks in the following statements : (a) Rutherford’s a -particle scattering experiment led to the discovery of the _____. (b) Isotopes have same _____ but different _____. (c) Neon and chlorine have atomic numbers 10 and 17 respectively. Their valencies will be _____ and _____ respectively. (d) The electronic configuration of silicon is _____ and that of sulphur is _____.

(a) nucleus (b) same atomic numbers, mass numbers (c) 0 and –1 (d) Si = 2,8,4 and S = 2,8,6

35. An element X has a mass number 4 and atomic number 2. Write the valency of this element?

As the K shell is completely filled, valency is zero.

Long Answer Questions

36. Why do helium, neon and argon have a zero valency?

Helium has two electrons in its only energy shell, while Argon and Neon have 8 electrons in their valence shells. These elements do not have any tendency to combine with other elements as they have maximum number of electrons in their valence shells. Therefore, they have zero valency.

37. The ratio of the radii of hydrogen atom and its nucleus is ~ 10 5 . Assuming the atom and the nucleus to be spherical,

(i) what will be the ratio of their sizes?

(ii) If atom is represented by planet earth ‘R e ’ = 6.4 ×10 6 m, estimate the size of the nucleus.

(i) Volume of the sphere = 4/3 πr 3

Let R be the radius of the atom and r be that of the nucleus.

Therefore ,R = 10 5 r

(ii) If the atom is represented by the planet earth (R e = 6.4×10 6 m) then the radius of the nucleus would be

38. Enlist the conclusions drawn by Rutherford from his a-ray scattering experiment.

The following conclusions were made from the Rutherford α-particle scattering experiment:

• As most of the α-particles passed through the gold foil undeflected, most of the space inside the atom is empty.
• Very few particles were deflected from their path, indicating that the positive charge of the atom occupies very little space.
• A very small fraction of α-particles were deflected by 180°,indicating that all the positive charges and mass of the gold atom were concentrated in a very small volume within the atom.

From the data he also calculated that the radius of the nucleus is about 105 times less than the radius of the atom.

39. In what way is the Rutherford’s atomic model different from that of Thomson’s atomic model?

Rutherford’s atomic model proposed that the electrons revolve around the nucleus in well-defined orbits. The center of the atom is positively charged and is called the nucleus. The model also proposed that the size of the nucleus is very small as compared to the size of the atom and nearly the entire mass of an atom is centred in the nucleus.

Thomson’s model of an atom was similar to that of a christmas pudding. The electrons are studded like currants in a positively charged sphere like christmas pudding and the mass of the atom was supposed to be uniformly distributed.

40. What were the drawbacks of Rutherford’s model of an atom?

Rutherford’s model failed to explain the stability of the atom. Any particle in a circular orbit would undergo an acceleration and the charged particles would radiate energy. Thus, the revolving electron would lose energy and finally fall into the nucleus. In other words, the atom should collapse.

41. What are the postulates of Bohr’s model of an atom?

The postulates of Neils Bohr’s about the model of an atom are as follows:

• Only certain special orbits known as discrete orbits of electrons, are allowed inside the atom.
• While revolving in discrete orbits the electrons do not radiate energy.

These orbits are called energy levels. Energy levels in an atom are shown by circles. These orbits are represented by the letters K,L,M,N,... or the numbers, n=1,2,3,4,....

42. Show diagrammatically the electron distributions in a sodium atom and a sodium ion and also give their atomic number.

As the atomic number of sodium atom is 11, it has 11 electrons. A positively charged sodium ion (Na + ) is formed by the removal of one electron from a sodium atom. Thus, a sodium ion has 11–1 = 10 electrons. The electronic configuration of sodium ion will be 2, 8. The atomic number of an element is equal to the number of protons in its atom. As, sodium atom and sodium ion have the same number of protons, therefore, the atomic number of both is 11.

43. In the Gold foil experiment of Geiger and Marsden, that paved the way for Rutherford’s model of an atom, ~ 1.00% of the α-particles were found to deflect at angles > 50º. If one mole of α-particles were bombarded on the gold foil, compute the number of α-particles that would deflect at angles less than 500.

% of α-particles deflected more than 50°=1% of α-particles.

% of α-particles deflected less than 50° = 100–1% =  99%

Number of α-particles bombarded = 1 mole = 6.022×10 23  particles

Number of particles that deflected at an angle less than 50°

Contact Form

Rutherford Alpha Particle Scattering Experiment

Table of Contents

Introduction

Rutherford scattering , also known as the alpha particle scattering experiment, is a type of nuclear physics experiment. It was conducted on November 28, 1911, by Ernest Rutherford and Hans Geiger in the Cavendish Laboratory at the University of Cambridge. The experiment aimed to identify whether atoms have a positive or negative electric charge by measuring how often alpha particles (helium nuclei) are scattered in various directions when they collide with a thin gold foil. Rutherford scattering is one of the fundamental processes that can be used to determine atomic structure and chemical properties. Rutherford scattering was originally known as Coulomb scattering because it relies solely on the static electric (Coulomb) potential to determine the minimum distance between particles. Because neither the alpha particles nor the gold nuclei are internally excited, the classical Rutherford scattering process of alpha particles against gold nuclei is an example of “elastic scattering.” The Rutherford formula also ignores the massive target nucleus’ recoil kinetic energy.

Fill Out the Form for Expert Academic Guidance!

Please indicate your interest Live Classes Books Test Series Self Learning

Verify OTP Code (required)

I agree to the terms and conditions and privacy policy .

Fill complete details

Target Exam ---

Rutherford Atomic Model – J. J. Thomson’s plum pudding model failed to explain certain experimental results related to the atomic structure of elements. Ernest Rutherford, a British scientist, conducted an experiment and, based on his findings, proposed the atomic structure of elements, resulting in the Rutherford Atomic Model.

Rutherford’s experiment involves bombarding a thin sheet of gold with -particles and then studying the trajectory of these particles after they collided with the gold foil. In his experiment, Rutherford directed high-energy streams of -particles from a radioactive source at a thin sheet of gold (100 nm thickness). He wrapped a fluorescent zinc sulphide screen around the thin gold foil to study the deflection of the -particles. Certain observations made by Rutherford contradicted Thomson’s atomic model. Rutherford observed how alpha particles scattered from a thin gold foil after passing beams of alpha particles through it. The configuration of electrons within an atom interested Ernest Rutherford. Rutherford devised a test for this purpose. Fast-moving alpha ()-particles were made to fall on a thin gold foil in this experiment. Because he wanted the layer to be as thin as possible, he picked gold foil. The thickness of this gold foil was approximately 1000 atoms.

Particles are helium ions that are doubly charged. The fast-moving -particles have a lot of energy because they have a mass of 4. The particles were expected to be deflected by the subatomic particles in the gold atoms. He didn’t expect to see large deflections because the -particles were much heavier than the protons. However, the -particle scattering experiment produced completely unexpected results.

The intriguing results, however, revealed that approximately one in every 2000 alpha particles was deflected by very large angles (over 90°), while the rest passed through with little deflection. Rutherford deduced from this that the majority of the mass was concentrated in a small, positively-charged region (the nucleus) surrounded by electrons. When a (positive) alpha particle got close enough to the nucleus, it was repelled strongly enough to bounce at high angles. The small size of the nucleus accounted for the small number of alpha particles repelled in this manner. Rutherford demonstrated,

Alpha particle scattering experiment

They used a thin gold foil with a thickness of 2.1× 10 -7 and placed it in the centre of a rotatable zinc sulphide detector and a microscope. They then fired a beam of 5.5MeV alpha particles from a radioactive source at the foil. As the alpha particles passed through the lead bricks, they were collimated. The scattering of these alpha particles after hitting the foil could be studied using the brief flashes on the screen. The results of this experiment were expected to teach Rutherford and his colleagues more about the structure of the atom.

The results of this experiment did not agree with Thomson’s plum-pudding model of the atom. Rutherford concluded that because alpha particles are positively charged, they required a strong repelling force to be deflected back. He went on to argue that in order for this to happen, the atom’s positive charge must be concentrated in the centre, rather than scattered as in the previously accepted model. As a result, when the incident alpha particle came very close to the positive mass in the atom’s centre, it would repel, causing a deflection. However, if it passes through at a reasonable distance from this mass, there will be no deflection and it will simply pass through.

Rutherford alpha scattering experiment

He conducts an experiment in which he bombards alpha particles into a thin sheet of gold and then observes their interaction with the gold foil as well as the trajectory or path taken by these particles. Rutherford conducts the experiment by passing very high streams of alpha-particles from a radioactive source, i.e. an alpha-particle emitter, through a thin sheet of gold with a thickness of 100 nm. He wrapped a screen of fluorescent zinc sulphide around the thin gold foil to examine the deflection caused by the alpha particles. Rutherford made some observations that contradict Thomson’s atomic model.

Rutherford’s Alpha Scattering Experiment yielded the following results:

First, he notices that the majority of the -particles bombarded towards the gold sheet pass through the foil without deflection, indicating that the majority of the space is empty. Some of the -particles were deflected through the gold sheet by very small angles, indicating that the positive charge in an atom is not distributed uniformly. In an atom, the positive charge is concentrated in a very small volume. Only a small percentage of the alpha-particles (1-2%) were deflected back, implying that only a small percentage of -particles had a nearly 180° angle of deflection. This demonstrates that the positively charged particles occupy a very small volume in comparison to the total volume of an atom.

Rutherford alpha particle scattering experiment discovered

Ernest Rutherford conducted an experiment involving the scattering of alpha particles. He bombarded the layered gold foil with positively charged alpha particles. He expected the alpha particles to revert back to the path they had taken when they were bombarded on the foil. However, the observed results were not the same. As a result, while the majority of the alpha particles pass through the foil, only a few particles experience small angle deflection.

Ernest Rutherford was interested in the arrangement of electrons in atoms. The fast-moving alpha particles were allowed to fall on the gold foil in the Rutherford experiment. The gold foil was hit with alpha particles. The thickness of this gold foil was approximately 1000 atoms. The alpha particles have a mass of four units and are doubly charged helium ions. This is a fast-moving particle that interacts with gold atom particles. Rutherford predicted that the subatomic particles in gold would revert the alpha particles. Because alpha particles are heavier than protons, it was expected that they would follow the same path as the protons. However, the observed results differed from what was expected.

From this, Rutherford proposed a model of the atom with a positive charge at the center of mass, which he dubbed a ‘nucleus.’ The nucleus contains the entire mass of the atom. Negatively charged electrons orbit the positively charged nucleus in orbits. The atomic nucleus was discovered thanks to Rutherford’s Alpha particle scattering experiment .

Question 1: What was the Rutherford scattering experiment’s conclusion?

Answer 1: Rutherford’s experiment demonstrated the existence of a nuclear atom, which consists of a small, positively-charged nucleus surrounded by empty space and then a layer of electrons that forms the atom’s outer shell. The majority of the alpha particles did pass directly through the foil.

Question 2: What were Rutherford’s findings from his alpha particle scattering experiment?

Answer 2: Because most of the -particles passed through the gold foil without being deflected, most of the space inside the atom is empty. Only a few particles were deflected from their path, indicating that the atom’s positive charge takes up very little space. A very small fraction of -particles was deflected by very large angles, indicating that the gold atom’s positive charge and mass were concentrated in a very small volume within the atom. The majority of the fast-moving -particles passed directly through the gold foil. The majority of the atom’s space is empty. The foil deflected some of the -particles at small angles.

Related content

Get access to free Mock Test and Master Class

Register to Get Free Mock Test and Study Material

Offer Ends in 5:00

Select your Course

Please select class.

Introduction

Rutherford was always curious in knowing about the arrangement of electrons in an atom. By performing an experiment using alpha particles and gold foil he came to some conclusions.

Experiments performed

Let us first learn something about the experiments he performed:

• A 1000 atoms thick gold foil was selected because he wanted as thin a layer as possible.
• Alpha particles are nothing but doubly charged helium ions. As its mass is 4u, the fast-moving alpha particles have a good amount of energy.
• He also expected that the alpha particles will be deflected as they are heavier than the protons. But what he observed was completely unexpected, he made the following observations:
• Most of the alpha particles passed straight through that gold foil.
• There was a deflection at a small angle by some of the alpha particles.
• A very small amount of alpha particles rebounded.

Rutherford concluded the following points after the observation:

• As there was very less deflection of alpha particles so he concluded that most of the space was empty in an atom.
• He also concluded that positive charge occupies a very less amount of space in an atom as very few particles were deflected from their path.
• A very small amount of alpha particles deflected with an angle of 180 0 , which indicated that the mass of the atom and the positive charge was concentrated at a small volume in an atom.

From all these observations he calculated that the radius of the nucleus is around 10 5 times less than the radius of the atom.

The following final model was put by Rutherford after all the observations:

• The nucleus is at the centre and is positively charged and nearly all the mass of the nucleus resides in the nucleus.
• Around the nucleus, electrons revolve in a circular path.
• The size of the nucleus is very less as compared to the size of the atom.

To learn more about Rutherford’s atomic model, register with BYJU’S now!

Put your understanding of this concept to test by answering a few MCQs. Click ‘Start Quiz’ to begin!

Select the correct answer and click on the “Finish” button Check your score and answers at the end of the quiz

Visit BYJU’S for all Chemistry related queries and study materials

Your result is as below

Request OTP on Voice Call

Leave a Comment Cancel reply

Your Mobile number and Email id will not be published. Required fields are marked *

Post My Comment

Register with BYJU'S & Download Free PDFs

Register with byju's & watch live videos.