Question

76. Among the following, ionic hydride is
(A) BH,
(B) SiH,
(C) MgH2
(D) PH,​

Answer 1

answer : option (C) MgH2

explanation : condition of ionic compound is

• electronegativity difference of combining atoms should be high.
• two atoms must be different in nature.
• ionisation potential of one atom must be small.
• electron affinity of second atom must be high.

here, in all options, only MgH2 is satisfying above all conditions.

ionisation potential of H is higher than Mg, electronegativity difference is also high in case of other options. and most important thing is that Mg is metal (electropositive character ) and H is considered as electronegative character that's why MgH2 is ionic hydride.