Give the chemical reaction for the preparation of water gas (syngas).

Match the correct option from Column-$A$ and Column-$B$.

Column-$A$	Column-$B$
$(1)$ Ionic hydride	$(p)$ $BeH_2$
$(2)$ Interstitial hydride	$(q)$ $TiH$
$(3)$ Electron-precise hydride	$(r)$ $CH_4$
$(4)$ Electron-rich hydride	$(s)$ $H_2O$
	$(t)$ $B_2H_6$

Given below are two statements,one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A:$ Isotopes of hydrogen have almost same chemical properties,but difference in their rates of reaction.
Reason $R:$ Isotopes of hydrogen have different enthalpy of bond dissociation.
In the light of the above statements,choose the most appropriate answer from the options given below:

Exhausted permutit does not contain ....... ion.

Assertion : Hydrogen combines with other elements by losing,gaining or sharing of electrons.
Reason : Hydrogen forms electrovalent and covalent bonds with other elements.

Under normal conditions,the hydrogen molecule is not reactive because .........