Question

Derive the molecular formula of aluminium oxide. Also calculate the molecular mass of the same compound.

(Al= 27 u )​

Answer 1

Answer:

Answer

Valency of an atom is the number of electrons that are required to be added or removed from the outermost shell of an atom to complete its octate.

Alumunium has an atomic number (Z) of 13

So, its electronic configuration is [Ne] 3s

2

3p

1

Hence, it needs to lose 3 electrons to attain stable configuration, hence its valency is three.

Oxygen has an atomic number (Z) of 18

So, its electronic configuration is [He]2s

2

3p

1

.

therefore, it needs to gain more electrons to attain stable ocate. Hence, its valency is 2