Anhydrous calcium chloride $(CaCl_2)$ is which type of compound?

Semi-water gas is a mixture of which of the following?

Which pair does not show hydrogen isotopes?

Arrange the following:
$(i)$ $CaH_2$,$BeH_2$ and $TiH_2$ in order of increasing electrical conductance.
$(ii)$ $LiH$,$NaH$ and $CsH$ in order of increasing ionic character.
$(iii)$ $H-H$,$D-D$ and $F-F$ in order of increasing bond dissociation enthalpy.
$(iv)$ $NaH$,$MgH_2$ and $H_2O$ in order of increasing reducing property.

Which of the following methods is used to prepare dihydrogen with purity greater than $99.95 \%$?

Hydrogen can be obtained from water by