Milk of magnesia is

Assertion : Barium is not required for normal biological function in humans.
Reason : Barium does not show variable oxidation states.

When $MgCl_2 \cdot 6H_2O$ is strongly heated,then it forms

Given below are two statements:
Statement $I$: None of the alkaline earth metal hydroxides dissolve in alkali.
Statement $II$: Solubility of alkaline earth metal hydroxides in water increases down the group.
In the light of the above statements,choose the most appropriate answer from the options given below:

$BeF_2$ is soluble in water,whereas the fluorides of other alkaline earth metals are insoluble. The reason for this is .......

What is the chemical formula for Plaster of Paris?