Which type of ions are present in the anhydrous mixture of $KF$ and $HF$?

How do you expect the metallic hydrides to be useful for hydrogen storage? Explain.

Which of the following substances is used in the laboratory for fast drying of neutral gases?

The hydride ions $({H^{-}})$ are isoelectronic with

Which of the following statements is not true for hydrogen:
$1)$ It exists as a diatomic molecule.
$2)$ It has one electron in the outermost shell.
$3)$ It can lose an electron to form a cation which can freely exist.
$4)$ It cannot form ionic compounds.

Isotope$(s)$ of hydrogen which emits low energy $\beta^{-}$ particle with $t_{1/2}$ value $> 12 \ years$ is/are :