Question

find the total no. of electrons n 4.2g of N3- ion. in the form of avagdro's no/

Answer 1

Molecular wt of N

3

−

=3×14=42 g

One ion of N

3

−

has valence electrons = 3×5+1=16

42 g N

3

−

=N

A

N

3

−

ion

valence electrons in N

A

ions = 16N

A

(where N

A

= Avogadro's number)

So, 1 g of N

3

−

will have valence electrons = 16N

A

/42

therefore,4.2g of N

3

−

ion will have valence electrons = 16N

A

×4.2/42=1.6N

A

.