Hydrogen can be prepared by the action of dil. $H_2SO_4$ on

The most dangerous method of preparing hydrogen would be by the action of $HCl$ and

State whether the following statements are True or False:
$(1)$ The metal and non-metal elements of $d$-block react with hydrogen to give molecular hydrides.
$(2)$ At normal temperature,dihydrogen reacts violently with dioxygen.

Which is an example of a molecular hydride?

Which of the following statement$(s)$ is/are correct:
$A$. $NaH$ is a non-volatile hydride
$B$. $MgH_2$ is a polymeric hydride
$C$. $NH_3$ is an electron-precise hydride
$D$. $H_2O$ is an electron-rich hydride

Identify the incorrect statement.