The hydride ion $H^{-}$ is isoelectronic with which of the following?

Which of the following statements is incorrect regarding saline hydrides?

Which of the following chemicals contains chlorine?

How can $D_2O$ be prepared from water? Mention the physical properties in which $D_2O$ differs from $H_2O$. Give at least three reactions of $D_2O$ showing the exchange of hydrogen with deuterium.

Which of the following is a hydride?

Calcium imide on hydrolysis will give gas $(B)$ which on oxidation by bleaching powder gives gas $(C)$. Gas $(C)$ on reaction with magnesium gives compound $(D)$. $(D)$ on hydrolysis gives again gas $(B)$. $(B)$,$(C)$ and $(D)$ are