Which of the following statements is true for all the alkali metals ?

Options

A. Their nitrates decomposes on heating to give the corresponding nitrites and oxygen.
B. Their chlorides are deliquescent and crystallise as hydrates.
C. They react with water for form hydroxide and hydrogen.
D. They readisy wth halogen to form ionic`-` halides,` M^(+)X^(-)`

Answer

C

Explanation

`(1)4LiNO_(3)rarr2Li_(2)O+4NO_(2)+O_(2)`
`2NaNO_(3)rarr2NaNO_(2)+O_(2)(` similar decomposition with the nitrates of `K, Rb` and `Cs)`
`(2)` Only LiCl is deliquescent and crystallises as a hydrate `LiCl.2H_(2)O`
`(3)2M+2H_(2)O rarr2M^(+)+2OH^(-)+H_(2)(M=` an alkali metal )
`(4)` Halides of Li are covalent in nature.