Structure of Atom

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

The total number of atomic orbitals in fourth energy level of an atom is

1. 8
2. 16
3. 32
4. 4

The energies E1 and E2 of two radiations are 25 eV and 50 eV respectively. The relation between their wavelengths i.e., 1 and 2 will be

1. 1 = 2
2. 1 = 2 2
3. 1 = 4 2
4. 1 = 12 2

If n = 6, the correct sequence for filling of electrons will be

1. ns (n-2)f (n-1)d np
2. ns (n-1)d (n-2)f np
3. ns (n-2)f np (n-1)d
4. ns np (n-1)d (n-2)f

A 0.66 kg ball is moving with a speed of 100 m/s. The associated wavelength will be (h = 6.6 10-34 J s)

1. 6.6 10-32 m
2. 6.6 10-34 m
3. 1.0 10-35 m
4. 1.0 10-32 m

Maximum number of electrons in a subshell of an atom is determined by the following

1. 2 + 1
2. 4 - 2
3. 2n2
4. 4 + 2

Which of the following is not permissible arrangement of electrons in an atom ?

1. n = 5, = 3, m = 0, s = +1/2
2. n = 3, = 2, m = -3, s = -1/2
3. n = 3, = 2, m = -2, s = -1/2
4. n = 4, = 0, m = 0, s = -1/2

If uncertainty in position and momentum are equal, then uncertainty in velocity is

1. 1m h
2. h
3. 12m h
4. h2

The measurement of the electron position is associated with an uncertainty in momentum, which is equal to 1 10-18 g cm s-1. The uncertainty in electron velocity is (mass of an electron is 9 10-28 g)

1. 1 105 cm s-1
2. 1 1011 cm s-1
3. 1 109 cm s-1
4. 1 106 cm s-1

Consider the following sets of quantum numbers: array|c|c|c|c|c| & n & l & m & s \ (i) & 3 & 0 & 0 & +1/2 \ (ii) & 2 & 2 & 1 & +1/2 \ (iii) & 4 & 3 & -2 & -1/2 \ (iv) & 1 & 0 & -1 & -1/2 \ (v) & 3 & 2 & 3 & +1/2 \ array Which of the following sets of quantum numbers are not possible?

1. (i), (ii), (iii) and (iv)
2. (ii), (iv) and (v)
3. (i) and (iii)
4. (ii), (iii) and (iv)