Question

Aufbau principle fails to explain the configuration of element with atomic number

Answer 1

Answer:

yep

Explanation:

Aufbau principle fails to explain the configuration of element with atomic number:

A18

B21

C24

D27

Solution

Chromium has atomic number 24.

Actual electronic configuration:

1

s

2

2

s

2

2

p

6

3

s

2

3

p

6

3

d

5

4

s

1

.

According to Aufbau:

1

s

2

2

s

2

2

p

6

3

s

2

3

p

6

3

d

4

4

s

2

.

Discripency is because of extra stability of half filled

(

d

5

)

orbitals.

Answer 2

Answer:

Explanation:

Is 18