NCERT Class 11 Chapter 2 Chemistry Structure of Atom MCQ

NCERT Class 11 Chapter 2 Chemistry Structure of Atom MCQ | Questions & Answers: With the help of this article, the candidates can take up the NCERT Class 11 Chapter 2 Chemistry Structure of Atom MCQ Quiz. To get instant results, make sure that you submit your answers at the end.

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1. Which of the scientist were able to prove that atom is no longer non-divisible?

A. Michael Faraday

B. Chadwick

C. Dalton

D. Thomson

2. Which of the following is never true for cathode rays ?

A. They are electromagnetic waves

B. They produce heat.

C. They produce mechanical pressure

D. They possess kinetic energy.

3. Cathode rays are deflected by

A. by both

B. an electric field only

C. magnetic field only

D. by none

4. Which of the following statement is not correct about the characteristics of cathode rays?

A. Characteristics of cathode rays depend upon the nature of gas present in the cathode ray tube

B. Characteristics of cathode rays do not depend upon the material of electrodes in cathode ray tube

C. They travel in straight line in the absence of an external electrical or magnetic field.

D. They start from the cathode and move towards the anode.

5. Which of the following statements about the electron is incorrect?

A. The mass of electron is equal to the mass of neutron

B. It is a basic constituent of all atoms.

C. It is a constituent of cathode rays.

D. It is negatively charged particle

6. While performing cathode ray experiments, it was observed that there was no passage of electric current under normal conditions. Which of the following can account for this observation ?

A. Air is a poor conductor of electricity under normal conditions

B. Carbon dioxide is present in air

C. Dust particles are present in air

D. None of the above

7. Which is not true with respect to cathode rays?

A. Move with speed same as that of light

B. Can be deflected by magnetic fields

C. Charged particles

D. A stream of electrons

8. What is the optimum conditions required to study the conduction of electricity through gases.

A. Low pressure and high voltage

B. Low pressure and low voltage

C. High pressure and high voltage

D. High pressure and low voltage

9. In discharge tube experiment stream of negatively charged particles travel from

A. cathode to anode

B. Electrons does not travel

C. anode to cathode

D. None of these

10. Millikan performed an experiment method to determine which of the following ?

A. Charge of the electron

B. Mass of the electron

C. e/m ratio of electron

D. Both (a) and (b)

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11. Which is correct statement about proton ?

A. Proton is ionized hydrogen atom

B. Proton is nucleus of deuterium

C. Proton is ionized hydrogen molecule

D. None of these

12. The lightest particle is

A. positron

B. neutron

C. proton

D. None of these

13. When beryllium is bombarded with alpha particles (Chadwick’s experiment) extremely penetrating radiations, which cannot be deflected by electrical or magnetic field are given out. These are

A. A beam of neutrons

B. Alpha rays

C. A beam of neutrons and protons

D. A beam of protons

14. The discovery of neutron became very late because

A. neutrons are chargeless

B. neutrons are fundamental particles

C. all of the above

D. None of these

15. Neutron is discovered by

A. Chadwick

B. Yukawa

C. Rutherford

D. Dalton

16.

A. Electrons, neutrons, protons

B. Electrons, protons, neutrons

C. Neutrons, protons, electrons

D. Protons, neutrons, electrons

17. Which of the following properties of atom could be explained correctly by Thomson Model of atom?

A. Overall neutrality of atom

B. Spectra of the hydrogen atom

C. Position of electrons, protons and neutrons in atom

D. Stability of atom.

18. When atoms are bombarded with alpha particles, only, a few in million suffer deflection, others pass out undeflected. This is because

A. the nucleus occupies much smaller volume compared to the volume of the atom

B. there is only one nucleus and large number of electrons

C. The force of attraction between alpha particle and oppositely charged electrons is very small

D. the force of repulsion on the moving alpha particle is small

19. Nucleons are

A. neutrons + protons

B. neutrons + protons + electrons

C. neutrons + electrons

D. only neutrons

20. The increasing order (lowest first) for the values of e/m (charge/mass) for

A. e, p, n, α

B. n, p, e, α

C. n, p, α, e

D. n, α, p, e

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21. The ionization enthalpy of hydrogen atom is 1.312 × 10⁶ J mol^-1. The energy required to excite the electron in the atom from n = 1 to n = 2 is

A. 8.51 × 10⁵ J mol^-1

B. 6.56 × 10⁵ J mol^-1

C. 7.56 × 10⁵ J mol^-1

D. 9.84 × 10⁵ J mol^-1

22. or a given principal level n = 4, the energy of its subshells is in the order

A. s < p < d < f

B. s > p > d > f

C. s < p < f < d

D. f < p < d < s

23. A gas absorbs a photon of 355 nm and emits at two wavelengths. If one of the emissions is at 680 nm, the other is at:

A. 518 nm

B. 1035 nm

C. 325 nm

D. 743 nm

24. Which of the following statements in relation to the hydrogen atom is correct?

A. 3s orbital is lower in energy than 3p orbital

B. 3p orbital is lower in energy than 3d orbital

C. 3s and 3p orbitals are of lower energy than 3d orbital

D. 3s, 3p and 3d orbitals all have the same energy

25. The magnetic quantum number specifies

A. Size of orbitals

B. Shape of orbitals

C. Orientation of orbitals

D. Nuclear Stability