write the electronic configuration of chromium and predict its number of subshelss,number of eletrons in subshell having l=0,number of electrons having n+l value=3,number of electrons in higest value of n.

Asked by mehrarora26 | 22nd Jul, 2015, 10:36: AM

Expert Answer:

The electron configuration for chromium is 1s22s22p63s23p64s23d4.

However, in the case of chromium there is one empty d sub orbital, one of the electrons from the 4s orbital will move up to the 3d orbital and make the the actual electron configuration 1s22s22p63s23p64s13d5

Therefore,

Predicted electron configurations: Cr (Z = 24): [Ar] 4s2 3d4

Actual electron configurations: Cr (Z = 24): [Ar] 4s1 3d5

Quantum number for chromium

n

m

Orbitals

Elements

Shell

n=1

0

0

1s

2

K

n=2

0

0

2s

2                 8

6

L

1

-1, 0, 1

2p

n=3

0

0

3s

2

6                13

5

M

1

-1, 0, 1

3p

2

-2, -1, 0, 1, 2

3d

n=4

0

0

4s

1                 1

N

1

-1, 0, 1

4p

 

2

-2, -1, 0, 1, 2

4d

 

3

-3, -2, -1, 0, 1, 2, 3

4f

 

(From the above table, we get,)

Predict its number of subshells

Ans: Chromium has 10 subshells viz - 1s, 2s, 2p, 3s, 3p, 3d, 4s, 4p, 4d, 4f

Number of electrons in subshell having l=0

Ans: There are 4 subshells and the first three sub shells (n=1, n=2 and n=3) has 2 electrons each and (n=4) has 1 electron.

Number of electrons having n + ℓ value=3

Ans: Total 8 electrons has n + ℓ value=3.

Number of electrons in highest value of n

Ans: Highest value is the last orbital (N orbital); n=4 i.e, 1 electron. 

 

Answered by Hanisha Vyas | 22nd Jul, 2015, 07:35: PM