One molecule of an 'ic' acid of a nonmetal having 5 electrons in valence shell reacts with a molecule of base to form a salt 'X'. The base corresponds to the metal with one electron in valence shell. If the salt so formed can react with the same base in 1 : 2 ratio, predict the formula of the salt 'X'.

Options

A. `K_(2)SO_(4)`
B. `Na_(2)HPO_(4)`
C. `KH_(2)PO_(4)`
D. `Na_(3)PO_(4)`

Answer

C

Explanation

The nonmetal with 5 valence electrons is phosphorus and 'ic' acid of phosphorus is phosphoric acid. Metal with one electron in valence shell forms base of the formula MOH. Since the salt can react with two molecules of base, the salt contains two replaceble hydrogens. The formula of salt'X' is `KH_(2)PO_(4)`.