Structure of Atom · Question 15

Two positively charged particles m1 and m2 have been accelerated across the same potential difference of 200 kV as shown below. [figure] [Given mass of m1 = 1 amu and m2 = 4 amu] The de Broglie wavelength of m1 will be x times of m2. The value of x is (nearest integer)

The hydrogen spectrum consists of several spectral lines in Lyman series (L1, L2, L3 ; L1 has lowest energy among Lyman series). Similarly it consists of several spectral lines in Balmer series (B1, B2, B3 ; B1 has lowest energy among Balmer lines). The energy of L1 is x times the energy of B1. The value of x is 10-1. (Nearest integer)

The wavelength of spectral line obtained in the spectrum of Li2+ ion, when the transition takes place between two levels whose sum is 4 and difference is 2, is

1. 1.14 10-6 cm
2. 2.28 10-6 cm
3. 1.14 10-7 cm
4. 2.28 10-7 cm

Given, (A) n = 5, ml = -1 (B) n = 3, l = 2, ml = -1, ms = + 12 The maximum number of electron(s) in an atom that can have the quantum numbers as given in (A) and (B) respectively are :

1. 4 and 1
2. 2 and 4
3. 26 and 1
4. 8 and 1

Which of the following statements regarding the energy of the stationary state is true in the following one-electron systems ?

1. +2.18 10-18 J for second orbit of He+ ion
2. +8.72 10-18 J for first orbit of He+ ion
3. -1.09 10-18 J for second orbit of H atom.
4. -2.18 10-18 J for third orbit of Li2+ ion

The work functions of two metals (MA and MB) are in the 1 : 2 ratio. When these metals are exposed to photons of energy 6 eV, the kinetic energy of liberated electrons of MA : MB is in the ratio of 2.642 : 1. The work functions (in eV) of MA and MB are respectively.

1. 3.1, 6.2
2. 1.5, 3.0
3. 2.3, 4.6
4. 1.4, 2.8

Identify the INCORRECT statements from the following : Choose the correct answer from the options given below :

1. A and D Only
2. A and C Only
3. A and B Only
4. B and C Only

The energy required by electrons, present in the first Bohr orbit of hydrogen atom to be excited to second Bohr orbit is J mol-1. Given: RH = 2.18 10-11 ergs.

1. 9.835 1012
2. 1.635 10-11
3. 1.635 10-18
4. 9.835 105

The energy of first (lowest) Balmer line of H atom is x J. The energy (in J) of second Balmer line of H atom is :

1. x1.35
2. 1.35x
3. x2
4. 2x

Given below are two statements : In the light of the above statements, choose the correct answer from the options given below :

1. Both Statement I and Statement II are true
2. Statement I is true but Statement II is false
3. Statement I is false but Statement II is true
4. Both Statement I and Statement II are false