Question

The formula of calcium nitride is _____________ .

Answer 1

Answer:

Ca3N2

Explanation:

The correct answer is

C

a

3

N

2

.

Let us see how we got the answer; Look at the electronic arrangement of Ca and N atom.

Ca ( Z= 20) has 20 electrons with following electronic configuration. 1

s

2

2

s

2

2

p

6

3

s

2

3

p

6

4

s

2

.

It loses two electron in its 4s subshell to achieve stability and forms ion

C

a

2

+

.

C

a

2

+

= 1

s

2

2

s

2

2

p

6

3

s

2

3

p

6

N ( Z=7) on the other hand has seven electrons and wants to gain three electrons to achieve stable noble gas configuration.Nitrogen atom on gaining three electrons forms negative nitride ion,

N

3

−

ion.

N ( Z=7) = 1

s

2

2

s

2

2

p

3

N

−

3

= 1

s

2

2

s

2

2

p

6

Answer 2

Answer:

Ca3N2 is the formula of calcium nitride