Question

The valency of sodium is one. Write the molecular formula for the following compounds of sodium.​
a) Sodium Oxide​
b) Sodium Sulphate​
c) Sodium Carbonate​

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Answer 1

a) Sodium Oxide:
The symbol for sodium is Na and for oxide, it is O.
The valency of sodium ion is 1 and oxide ion is 2.
Upon criss-crossing the valencies and writing them as subscripts, the chemical formula of sodium oxide comes to be as ${\mathrm{Na}}_{2}O.$

b)The symbol for sodium is Na and for sulphate, it is ${\mathrm{SO}}_4.$
The valency of sodium ion is 1 and sulphate ion is 2.
Upon criss-crossing the valencies and balancing them, we get the formula of the compound, the chemical formula of sodium sulphate comes to be ${\mathrm{Na}}_2{\mathrm{SO}}_4$

c) Sodium Carbonate:
The symbol for sodium is Na and for carbonate, it is ${\mathrm{CO}}_3$.
The valency of sodium ion is 1 and carbonate ion is 2.
Upon criss-crossing the valencies and writing them as subscripts, the chemical formula of sodium carbonate comes to be as ${\mathrm{Na}}_2{\mathrm{CO}}_3$