0.715 g of Na2CO3 xH2O is required 20mL of semi-normal hydrochloric acid solution for complete reaction. Find the value of x

The value of x : 2

Semi-normal Hydrochloric acid solution = 0.5 N = 0.5 M

for titration :

M₁V₁n₁=M₂V₂n₂(1=HCl,2=Na₂CO₃)

MW Na₂CO₃.xH₂O=143

MW Na₂CO₃.xH₂O = MW Na₂CO₃+ MW xH₂O = 143

MW Na₂CO₃ = 106 g/mol

MW xH₂O = 18x

Equation :

sodium (na), for example, has one electron in its valence shell. this is an unstable state because that valence shell needs eight electrons to be full. in order to fill its valence shell, find a way to add seven electrons to its valence shell