#### Public one mark questions Quantum Mechanical Model of Atom - III

11th Standard

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Chemistry

Time : 00:20:00 Hrs
Total Marks : 25

Part - A

25 x 1 = 25
1. The Bohr's radius of Li2+ of 2nd orbit is ________________

(a)

0.529 $\mathring{A}$

(b)

0.0753$\mathring{A}$

(c)

0.7053$\mathring{A}$

(d)

0.0529$\mathring{A}$

2. The formula used to calculate the Bohr's radius is_________________

(a)

$r_n={(-13.6)Z^2\over n^2}eV \ atom^{-1}$

(b)

$r_n={(0.529)n^2\over z}A$

(c)

$r_n={(-1312.8)Z^2\over n^2}kJ \ mol^{-1}$

(d)

$r_n={(+1312.8)n^2\over Z^2}kJ \ mol^{-1}$

3. Who proposed the dual nature of light to all forms of matter?

(a)

John Dalton

(b)

Neils Bohr

(c)

Albert Einstein

(d)

J. J. Thomson

4. de Broglie equation is________________

(a)

E=$h \ \gamma$

(b)

E=mc2

(c)

$\gamma ={E_2-E_1 \over h}$

(d)

$\lambda ={h\over mv}$

5. The crystal used in Davison and Germer experiment is____________________

(a)

nickel

(b)

zinc sulphide

(c)

gold foil

(d)

NaCI

6. Which one of the following is the time independent Schrodinger wave equation?

(a)

$\triangle x.\triangle p\ge {h\over 4\pi}$

(b)

${\partial^2\psi\over \partial x^2}+{\partial^2\psi\over \partial y^2}+{\partial^2\psi\over \partial z^2}+{8\pi^2m\over h^2}=0$

(c)

${\partial^2\psi\over \partial x^2}+{\partial^2\psi\over \partial y^2}+{\partial^2\psi\over \partial z^2}+{8\pi^2m\over h^2}(E-V)\psi=0$

(d)

$\hat{H}\psi-E\psi=-{8\pi^2m\over h^2}$

7. Match the list-I and list-II correctly using the code given below the list.

List-I List-II
A. Principal quantum number 1.represents the directional orientation of orbital
B. Azimuthal quantum number 2.represents the spin of the electron
C. Magnetic quantum number 3.represents the main shell
D. Spin quantum number 4.represents the sub shell
(a)
 A B C D 3 4 1 2
(b)
 A B C D 4 2 3 1
(c)
 A B C D 2 1 4 3
(d)
 A B C D 1 3 2 4
8. The maximum number of electrons that can be accommodated in N shell is_____________

(a)

8

(b)

18

(c)

32

(d)

36

9. The maximum number of electrons that can be accommodated in f orbital is __________________

(a)

10

(b)

14

(c)

16

(d)

6

10. When l= 0, the number of electrons that can be accommodated in the subshell is_______________

(a)

0

(b)

2

(c)

6

(d)

8

11. Which one of the quantum number is used to calculate the angular momentum of an atom?

(a)

n

(b)

m

(c)

l

(d)

s

12. What is the formula used to calculate the angular momentum?

(a)

$\sqrt{l(l+1)}{h\over 2\pi}$

(b)

$mvr\over 2\pi$

(c)

$mvr\over 2$

(d)

m.$\triangle v$

13. Which of the following provides the experimental justification of magnetic quantum number?

(a)

Zeeman effect

(b)

Stark effect

(c)

Uncertainty principle

(d)

Quantum condition

14. What are the values of n, I, m and s for 3px electron?

(a)

3,2,1,0

(b)

3,1,-1,+1/2

(c)

3,2,+1,-1/2

(d)

3,0,0,+1/2

15. Which of the following is the actual configuration of Cr (Z = 24)?

(a)

1s2 2s2 2p6 3s2 3p6 3d4 4s2

(b)

1s2 2s2 2p6 3s2 3p6 3d5 4s1

(c)

1s2 2s2 2p6 3s2 3p6 3d6

(d)

1s2 2s2 2p6 3s2 3p6 3d5 4s3

16. In a sodium atom (atomic number = 11 and mass number = 23) and the number of neutrons is___________.

(a)

equal to the number of protons

(b)

less than the number of protons

(c)

greater than the number of protons

(d)

none of these

17. The idea of stationary orbits was first given by_________.

(a)

Rutherford

(b)

J.J. Thomson

(c)

Niels Bohr

(d)

Max Planck

18. de Broglie equation is______.

(a)

$\lambda=\frac{h}{mv}$

(b)

$\lambda=\frac{hv}{m}$

(c)

$\lambda=\frac{mv}{h}$

(d)

$\lambda=hmv$

19. The orbital with n = 3 and l=2 is____.

(a)

3s

(b)

3p

(c)

3d

(d)

3j

20. The outermost electronic configuration of manganese (at. no. = 25) is___.

(a)

3d5 4s2

(b)

3d6 4s1

(c)

3d7 4so

(d)

3d6 4s2

21. The maximum number of electrons in a sub-shell is given by the equation________.

(a)

n2

(b)

2n2

(c)

2l- 1

(d)

2l+1

22. Which of the following statements is correct for an electron that has the quantum numbers n = 4 and in = -2.

(a)

The electron may be in 2p orbital

(b)

The electron may be in 4d orbital

(c)

The electron is in the second main shell

(d)

The electron must have spin quantum number as $+\frac{1}{2}$

23. Assertion(A): Cr with electronic configuration [Ar] 3d5 4s1 is more stable than [Ar] 3d4 4s2.
Reason(R): Half filled orbitals have been found to have extra stability than partially filled orbitals.

(a)

A and R are correct and R is the correct explanation of A.

(b)

A and R are correct but R is not the correct the explanation of A.

(c)

A is correct but R is wrong.

(d)

A is wrong but R is correct.

24. Assertion (A): Copper (Z = 29) with electronic configuration [Ar] 4s1 3d10 is more stable than [Ar] 4s2 3d9.
Reason (R): Copper with [Ar] 4s1 3d10 is more stable due to symmetrical distribution and exchange energies of d electrons.

(a)

A and R are correct and R is the correct explanation of A.

(b)

A and R are correct but R is not the correct explanation of A.

(c)

A is correct but R is wrong.

(d)

A is wrong but R is correct.

25. Assertion: Helium has the highest value of ionization energy among all the elements known
Reason: Helium has the highest value of electron affinity among all the elements known

(a)

Both assertion and reason are true and reason is correct explanation for the assertion.

(b)

Both assertion and reason are true but the reason is not the correct explanation for the assertion

(c)

Assertion is true and the reason is false

(d)

Both assertion and the reason are false