Q. 314.0( 26 Votes )

# How many electrons in an atom may have the following quantum numbers?

(a) *n* = 4, *m*_{s}= – 1/2

(b) *n* = 3, *l* = 0

_{s}

Answer :

(a) Total number of electrons in an atom can be found out by the following relationship

n_{e} = 2n^{2}

Total no of electrons when n=4, then n = 2× 4^{2} = 32 & half of them have m_{s} = -1/2

(b) When n = 3, L=0 means 3s orbital which can have 2 electrons.

Rate this question :

The bromine atom possesses 35 electrons. It contains 6 electrons in 2*p* orbital, 6 electrons in 3*p* orbital and 5 electron in 4*p* orbital. Which of these electron experiences the lowest effective nuclear charge?

Among the following pairs of orbitals which orbital will experience the larger effective nuclear charge?

(i) 2*s* and 3*s*

(ii) 4*d* and 4*f*

(iii) 3*d* and 3*p*

If the velocity of the electron in Bohr’s first orbit is 2.19 × 10^{6} ms^{–1}, calculate the de Broglie wavelength associated with it.

The unpaired electrons in Al and Si are present in 3*p* orbital. Which electrons will experience more effective nuclear charge from the nucleus?

Calculate the wavelength of an electron moving with a velocity of 2.05 × 10^{7} m s^{–1}.