Q. Among $CaH_{2},\ NH_{3},\ NaH\ and\ B_{2}H_{6},$ which are covalent hydride?
A) $NH_{3}and\ B_{2}H_{6}$
B) $NaH\ and\ CaH_{2}$
C) $NaH\ and\ NH_{3}$
D) $CaH_{2}\ and\ \ B_{2}H_{6}$
Explanation
(a)
Hydrides are binary compounds of hydrogen. These can be classified in four groups viz :
(i) Ionic hydrides e.g., $NaH,\ CaH_{2},\ LiH\ etc.$
(ii) Covalent hydrides e.g., $B_{2}H_{6},\ NH_{3},\ SbH_{3}\ etc.$
(iii) Polynuclear hydrides e.g., $LiAlH_{4},\ NaBH_{4}\ etc.$
(iv) Interstitial hydrides, in which hydrogen is trapped in the interstial spaces of transition metals.
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.