Structure of Atom

The frequency of radiation emitted when the electron falls from n = 4 to n = 1 in hydrogen atom will be (Given ionization energy of H = 2.18 10-18 J atom-1 and h = 6.625 10-34 J s)

1. 1.54 1015 s-1
2. 1.03 1015 s-1
3. 3.08 1015 s-1
4. 2.00 1015 s-1

The radioactive isotope 6027Co which is used in the treatment of cancer can be made by (n, p) reaction. For this reaction the target nucleus is

1. 5928Ni
2. 5927Co
3. 6028Ni
4. 6027Co

The value of Planck's constant is 6.63 10-34 J s. The velocity of light is 3.0 108 m s-1. Which value is closest to the wavelength in nanometers of a quantum of light with frequency of 8 1015 s-1 ?

1. 2 10-25
2. 5 10-18
3. 4 101
4. 3 107

In hydrogen atom, energy of first excited state is -3.4 eV. Then find out K.E. of same orbit of hydrogen atom

1. +3.4 eV
2. +6.8 eV
3. -13.6 eV
4. +13.6 eV

23592U, nucleus absorbs a neutron and disintegrates into 13954Xe, 9438Sr and x so, what will be product x?

1. 3-neutrons
2. 2-neutrons
3. -particle
4. -particle

The following quantum numbers are possible for how many orbitals : n = 3, l = 2, m = +2 ?

1. 1
2. 2
3. 3
4. 4

If a abX species emits first a positron, then two and two particles and in the last, one is also emitted and gets converted to cdY species. So correct relation is

1. c = a - 12, d = b - 5
2. c = a - 5, d = b - 1
3. c = a - 6, d = b - 0
4. c = a - 4, d = b - 2

For given energy, E = 3.03 10-19 Joules corresponding wavelength is (h = 6.626 10-34 J sec, c = 3 108 m/sec)

1. 65.6 nm
2. 6.56 nm
3. 3.4 nm
4. 656 nm

Isoelectronic species are

1. CO, CN-, NO+, C22-
2. CO-, CN, NO, C2-
3. CO+, CN+, NO-, C2
4. CO, CN, NO, C2