Question

Q203) In an atom, which has 2K, 8L, 18M and 2N electrons in the ground state. The total number of electrons having magnetic quantum number, m = 0 is

Q203) In an atom, which has 2K, 8L, 18M and 2N electrons in the ground state. The total number of electrons having magnetic quantum number, m = 0 is

SOLUTION

2K electron i.e. 2 electron in n =1

∴ values of l = 0 and m = 0

for m= 0, 2 electrons

8K electron .i.e n = 2 fully filled

∴ values of l = 0,1

for l =0 , m = 0

and l= 1 , m = +1 ,0 , -1

18M electron .i.e n = 3 fully filled

∴ values of l = 0,1, 2

for l =0 , m = 0

and l= 1 , m = +1 ,0 , -1

and l =2 m =+2, +1, 0, -1, -2

2N electron i.e n =4 only two electrons

∴ values of l = 0,1,2,3

have subhsell 4s, thus m =0

Now total m= 0 appear above =7

each m=0 have two electrons = 7×2 = 14 electrons

Answer:(d)