$X$-ray tube windows are made using which of the following metals?

Pure anhydrous $MgCl_2$ can be prepared from the hydrated salt by

In the hardening stage of Plaster of Paris, the compound formed is:

Select the incorrect statement about alkaline earth metals.

$A$ solid compound $X$ on heating gives $CO_2$ gas and a residue. The residue mixed with water forms $Y$. On passing an excess of $CO_2$ through $Y$ in water,a clear solution $Z$ is obtained. On boiling $Z$,compound $X$ is reformed. The compound $X$ is

Epsom salt is a hydrate of which of the following?