Among $CaH_2$,$NH_3$,$NaH$,and $B_2H_6$,which are covalent hydrides?

Identify the catalyst used to transform carbon monoxide from water gas into carbon dioxide.

What is the correct order of reactivity for different forms of hydrogen?

Which one of the following statements is incorrect $?$

Saline hydrides react explosively with water. Such fires can be extinguished by:

Which of the following sets are correctly matched?
$(i)$ $B_2H_6$ - electron deficient hydride
$(ii)$ $NH_3$ - electron precise hydride
$(iii)$ $H_2O$ - electron rich hydride