The formula weight of an acid is `82.0.100 cm^(3)` of a solution of this acid containing `39.0 g` of the acid per litre were completely neutralised by `95.0 cm^(3)` of aqueous `NaOH` containing `40.0 g` of `NaOH` per litre. What is the basicity of the acid?

Explanation

Suppose the equivalent wt. of the acid = E
`therefore" Normality of the acid solution"=(39gL^(-1))/(E)`
Eq. wt. of NaOH = 40
`therefore" Normality of NaOH solution"=(40gL^(-1))/(40)=1N`
`"Applying "underset("(Acid)")(N_(1)xxV_(1))=underset("(NaOH)")(N_(2)xxV_(2))`
`(39)/(E)xx100=1xx95 or E=41.0`
`"Basicity of the acid"=("Formula wt.")/("Equivalent wt.")=(82.0)/(41.0)=2`