Structure of the atom Worksheet-1

Structure of the atom Worksheet-1

1. What is the nature of the rays travelling from cathode to the anode in the discharge tube?

A. The rays consist of negatively charged particles

B. The rays consist of positively charged particles

C. The rays consist of neutral particles

2. Do anode rays also originate from the anode?

A. Yes, they originate from anode

B. No, they originate from the gas filled in the discharge tube

C. They can be originated either from anode or cathode

3. Of all the subatomic particles which is the heaviest particle?

A. Electron        B. Proton           C. Neutron

4. Who discovered anode rays?

A. J. J. Thomson

B. E. Goldstein

C. James Chadwick

5. Is air a good conductor of electricity?

A. Yes                 B. No

6. Is atom as a whole positively charged?

A. Yes

B. No

C. Depends on the type of element

7. What was the source of emission of alpha particles needed for Rutherford experiment?

A. Radium         B. Polonium      C. Thorium       D. Plutonium

8. Are alpha particles same as the helium atoms?

A. No, they are similar to helium nucleus and not helium atoms

B. Yes, they are similar to helium atoms

C. No, they are similar to hydrogen atoms and not helium atoms

D. No

9. Which metal was used by Rutherford for making foil?

A. Silver             B. Gold               C. Platinum       D. Copper

10. Name the substance which was used for coating the photographic plate.

A. Ferrous sulphide                     B. Sodium sulphide

C. Potassium sulphide                D. Zinc sulphide

Answer:

1. A

2. B

3. C

Explanation: Mass of electron is 0.000548597 a.m.u. or 9.1 x 10^-31 kg.

Mass of proton is 1.0072766 a.m.u. or 1.6726 x 10^-27 kg.

Mass of neutron is 1.0086654 a.m.u. or 1.6749 x 10^-27 kg. 

Neutron is heaviest among all the sub atomic particles.

4. B

Explanation: E. Goldstein discovered the anode rays. He called these rays canal rays

5. B

Explanation: No, air is a poor conductor of electricity

6. B

Explanation: An atom is neutral. Number of protons in an atom is equal to number of electrons.

7. A

Explanation: Radium (Ra)

8. A

Explanation: An alpha particle is a particle made up of two protons and two neutrons. Since this configuration is similar to that of a helium nucleus, it is often referred to as a helium nucleus

9. B

10. D

Explanation: Zinc sulphide