Structure of Atom

Calculate the energy in joule corresponding to light of wavelength 45 nm. (Planck's constant, h = 6.63 10-34 J s, speed of light, c = 3 108 m s-1)

1. 6.67 1015
2. 6.67 1011
3. 4.42 10-15
4. 4.42 10-18

Be2+ is isoelectronic with which of the following ions?

1. H+
2. Li+
3. Na+
4. Mg2+

What is the maximum number of electrons that can be associated with the following set of quantum numbers ? n = 3, l = 1 and m = -1

1. 4
2. 2
3. 10
4. 6

Based on equation E = -2.178 10-18 J ( Z2n2 ), certain conclusions are written. Which of them is not correct ?

1. Equation can be used to calculate the change in energy when the electron changes orbit.
2. For n = 1, the electron has a more negative energy than it does for n = 6 which means that the electron is more loosely bound in the smallest allowed orbit.
3. The negative sign in equation simply means that the energy of electron bound to the nucleus is lower than it would be if the electrons were at the infinite distance from the nucleus.
4. Larger the value of n, the larger is the orbit radius.

The value of Planck's constant is 6.63 10-34 J s. The speed of light is 3 1017 nm s-1. Which value is closest to the wavelength in nanometer of a quantum of light with frequency of 6 1015 s-1 ?

1. 50
2. 75
3. 10
4. 25

According to law of photochemical equivalence the energy absorbed (in ergs/mole) is given as (h = 6.62 10-27 ergs, c = 3 1010 cm s-1, NA = 6.02 1023 mol-1)

1. 1.196 108
2. 2.859 105
3. 2.859 1016
4. 1.196 1016

The orbital angular momentum of a p-electron is given as

1. h 2
2. 3 h2
3. 32 h
4. 6 h2

Maximum number of electrons in a subshell with l = 3 and n = 4 is

1. 14
2. 16
3. 10
4. 12

The correct set of four quantum numbers for the valence electron of rubidium atom (Z = 37) is

1. 5, 1, 1, + 12
2. 6, 0, 0, + 12
3. 5, 0, 0, + 12
4. 5, 1, 0, + 12

According to the Bohr theory, which of the following transitions in the hydrogen atom will give rise to the least energetic photon ?

1. n = 6 to n = 1
2. n = 5 to n = 4
3. n = 6 to n = 5
4. n = 5 to n = 3