Which of the following alkaline earth metals forms complex salts?

The white enamel of our teeth is composed of:

Bleaching powder is correctly represented as

Identify the correct statements from the following:
$I$. All alkaline earth metals give hydrides on heating with hydrogen.
$II$. Calcium hydroxide is used to purify sugar.
$III$. $BeCl_2$ is a dimer in gaseous phase.

The ‘milk of magnesia’ used as an antacid is chemically

Statement $A$: Calcium chloride $(CaCl_2)$ is not useful for drying alcohols or $NH_3$.
Reason $R$: $CaCl_2$ is not a good desiccant.