## Question

### Solution

Correct option is

Hund’s rule

Paring in degenerate orbitals cannot take place until each of them is singly occupied (Hund’s rule).

#### SIMILAR QUESTIONS

Q1

The atomic spectrum of hydrogen is found to contain a series of lines at wavelengths 656.46, 486.27, 434.17 and 410.29 nm. What will be the wavelength of the next line in the series?

Q2

Calculate the energy required for the process The ionization energy for the H-atom in the ground state is

2.18 × 10–18 J atom–1.

Q3

A photon of wavelength 1.4 Å collides with an electron. After collision, the wavelength of the photon is found to be 2.0 Å. Calculate the energy of the scattered electron.

Q4

If the binding energy of electrons in a metal is 250 kJ mol–1, what should be threshold frequency of the striking photons?

Q5

What is the minimum uncertainty in the position of a bullet of a mass 5g that is known to have a speed somewhere between 550,00000 and 550,00001 ms–1?

Q6

When would de Broglie wavelength of a moving electron become equal to that of a moving proton? Mass of electron =

9.1095 × 10–31 kg and mass of proton = 1.6725 × 10–27 kg.

Q7

How fast is an electron moving if it has a wavelength equal to the distance it travels in one second?

(mass of electron = 9.1 × 10–31 kg)

Q8

To which orbit the electron in the hydrogen atom will jump on absorbing 12.1 eV of energy?

Q9

The valence shell electron of sodium has the quantum numbers

(nlms)

Q10

The ratio of the energy of photon of λ = 2000 Å to that of λ = 4000 Å is