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Question Bank No: 2

1. The uncertainty in the position of a moving bullet of mass 10 gm is $10^{- 5} m .$ Calculate the uncertainty in its velocity.

a)		5.2 x $10^{- 28} m / \sec$
b)		3.0 x $10^{- 28} m / \sec$
c)		5.2 x $10^{- 22} m / \sec$
d)		3 x $10^{- 22} m / \sec$

2. It is not true that

a)		the wavelength associated with an electron is longer than that of proton, if they have the same speed
b)		violet radiations have a longer wavelength than red radiations
c)		the energy of light with $λ = nm$ is lower than that with $λ = 500 nm$
d)		spectrum of an atom is known as line spectrum

3. The momentum associated with a photon of frequency v is
where 'h' is Plancks constant and 'c' is velocity of light

a)		hv/c
b)		hc/v
c)		vc/h
d)		h/vc

4. Which of the following quantum number represents an impossible arrangement?
$\begin{matrix} n & l & m & s \end{matrix}$

a)		$\begin{matrix} 3 & 2 & - 2 & 1 / 2 \end{matrix}$
b)		$\begin{matrix} 4 & 0 & 0 & 1 / 2 \end{matrix}$
c)		$\begin{matrix} 3 & 2 & - 3 & 1 / 2 \end{matrix}$
d)		$\begin{matrix} 5 & 3 & 0 & - 1 / 2 \end{matrix}$

5. An electron has kinetic energy of ${2.14 \times 10}^{- 22} J$ . Its de-Brogile wavelength will be nearly ( $m_{e} = {9.1 \times 10}^{- 31}$ kg)

a)		${9.28 \times 10}^{- 4} m$
b)		${9.28 \times 10}^{- 7} m$
c)		${9.28 \times 10}^{- 8} m$
d)		${9.28 \times 10}^{- 10} m$

6. According to Bohr's theory, the energy required for the transition of H atom from n=6 to n = 8 state is

a)		equal to energy required for the transition from n = 5 to n = 7 state
b)		larger than in (A)
c)		less than in (A)
d)		equal to energy for the transition from n = 7 to n = 9 state

7. The energy of a photon is given as, $Δ E / atom = {3.03 \times 10}^{- 19} J {atom}^{- μ}$ then, the wavelength ( $λ$ ) of the photon is

a)		65.6 nm
b)		656 nm
c)		0.656 nm
d)		6.56 nm

8. The De- Broglie wavelength of a particle with mass 1g and velocity 100m/s is

a)		${6.63 \times 10}^{- 33} m$
b)		${6.63 \times 10}^{- 34} m$
c)		${6.63 \times 10}^{- 35} m$
d)		${6.65 \times 10}^{- 35} m$

9. Which of the following has more unpaired d-electrons?

a)		${Zn}^{+}$
b)		${Fe}^{2 +}$
c)		${Ni}^{3 +}$
d)		${Cu}^{+}$

10. The four quantum numbers of the valency electron of potassium are

a)		4,1,1,1/2
b)		4,0,0,1/2
c)		4,1,0,1/2
d)		4,4,0,1/2

11. The first emission line in the atomic spectrum of hydrogen in the Balmer series appears at

a)		$\frac{9 R}{400} {cm}^{- 1}$
b)		$\frac{7 R}{144} {cm}^{- 1}$
c)		$\frac{3 R}{4} {cm}^{- 1}$
d)		$\frac{5 R}{36} {cm}^{- 1}$

12. If the radius of first Bohr orbit be $a_{0}$ , then the radius of third Bohr orbit would be

a)		${3 \times a}_{0}$
b)		${6 \times a}_{0}$
c)		${9 \times a}_{0}$
d)		${1 / 9 \times a}_{0}$

13. Wave nature of electron was demonstrated by

a)		Schrodinger
b)		De-Brogile
c)		Davisson
d)		Heisenberg

14. Which of the following is the electronic configuration of ${Cu}^{2 +} (Z = 29)$ ?

a)		$[Ar] {4 s}^{1} {3 d}^{8}$
b)		$[Ar]$ ${4 s}^{2} {3 d}^{10} {4 p}^{1}$
c)		$[Ar]$ ${4 s}^{1} {3 d}^{10}$
d)		$[Ar]$ ${3 d}^{9}$

15. The configuration ${1 s}^{2} {2 s}^{2} {2 p}^{5} {3 s}^{1}$ shows

a)		ground state of fluorine
b)		excited state of fluorine
c)		excited state of neon atom
d)		excited state of $O_{2}^{-}$ ion

16. The radius of the atom is of the order of

a)		$10^{- 10}$
b)		$10^{- 13}$
c)		$10^{- 15}$
d)		$10^{- 8}$

17. Azimuthal quantum number determines the

a)		size
b)		spin
c)		orientation
d)		angular momentum of orbitals

18. Splitting of spectral lines under the influence of magnetic field is called

a)		Stark effect
b)		Zeeman effect
c)		Photoelectric effect
d)		none of these

19. The set of quantum numbers not applicable to an electron is

a)		1,1,1, $+ \frac{1}{2}$
b)		1,0,0, $+ \frac{1}{2}$
c)		1,0,0, $- \frac{1}{2}$
d)		2,0,0, $+ \frac{1}{2}$

20. Which one of the following pairs of atoms/atom-ion have identical ground state configuration?

a)		${Li}^{+}$ and ${He}^{+}$
b)		${Cl}^{-}$ and $Ar$
c)		Na and K
d)		${Fe}^{+}$ and Ne

21. The number of electrons in 3d shell for element with atomic number 26 is

a)		4
b)		6
c)		8
d)		10

22. An electron has a spin quantum number $+ \frac{1}{2}$ and a magnetic quantum number -1. It can not be present in

a)		d-orbital
b)		f-orbital
c)		p-orbital
d)		s-orbital

23. With increasing principle quantum number, the energy difference between adjascent energy levels in H atom

a)		decreases
b)		increases
c)		remains constant
d)		decreases for low value of Z and increases for higher value of Z

24. The magnatic quantum number represents

a)		Size of the Orbital
b)		Spin angular momentum
c)		Orbital angular momentum
d)		Spatial orientation of Orbital

25. The number of elctrons in the M shell of the element with Z=24 is

a)		24
b)		12
c)		13
d)		8

26. The quantum number for the outer electron of an atom is are given by n=2, l=0, m=0, s =+ $\frac{1}{2}$

a)		Lithium
b)		Helium
c)		Hydrogen
d)		Boron

27. NaCl imparts a yellow colour to the Bunsen flame. This can be due to

a)		low ionisation energy of sodim
b)		Sublimation of metalic sodium to give yellow colour
c)		Emission of excess energy absorbed as a radiation in the visible region
d)		Photo sensitivity of Sodim

28. "The exact path of electron 2p orbital cannot be determined". The above statement is based upon

a)		Hund's Rule
b)		Bohr's Rule
c)		Uncertainity Principle
d)		Aufbau Principle

29. The number of sperical nodes in 3p orbitals are

a)		1
b)		3
c)		0
d)		2

30. The energy of hydrogen atom in it's ground state is -13.6eV. The energy of the level corresponding to the quantum number n=5 is

a)		-0.54 eV
b)		-5.4 eV
c)		-0.85 eV
d)		-2.72 eV

31. If uncertainity in the position of an electron is zero, the uncertainity in its momentum would be

a)		Zero
b)		$\geq \frac{h}{4 \prod}$
c)		$< \frac{h}{4 \prod}$
d)		Infinite

32. The total number of orbitals in a shell with principal quantum number 'n' is

a)		2n
b)		$2 n^{2}$
c)		$n^{2}$
d)		n+1

33. The configuration ${1 s}^{2} {2 s}^{2} 2 p^{5} {3 s}^{1}$ shows

a)		ground state flourine
b)		excited state of flourine
c)		excited state of neon atom
d)		excited state of $O_{2}^{-}$

34. If the radius of the first Bohr orbit be $a_{0}$ , then the radius of third Bohr orbit would be

a)		$3 a_{0}$
b)		${ba}_{0}$
c)		$9 a_{0}$
d)		$\frac{1}{9} a_{0}$

35. The highest number of unpaired electrons are present in

a)		Fe
b)		${Fe}^{4 +}$
c)		${Fe}^{2 +}$
d)		${Fe}^{3 +}$

36. Which of the following ions has the maximum magnetic moment

a)		${Mn}^{2 +}$
b)		${Fe}^{2 +}$
c)		${Ti}^{2 +}$
d)		${Cr}^{2 +}$

37. In a hydrogen atom, if the energy of an electron in the ground state is 13.6 eV, then that in the 2nd excited state is

a)		1.51 eV
b)		3.4 eV
c)		6.04 eV
d)		13.6 eV

38. The maximum number of electrons in a subshell is given by

a)		4l-2
b)		4l+2
c)		2l+1
d)		$2 n^{2}$