Lithium aluminium hydride can be prepared from the reaction of

Which of the following is the atomic number of a metal?

In the reaction $M + O_2 \to MO_2$ (superoxide),the metal $M$ is

Match the following metals with their oxidizing flame color.

Compound	Flame color
$1$. $Li$	$a$. Crimson red
$2$. $K$	$b$. Violet
$3$. $Cs$	$c$. Blue

The magnetic behaviour of $Li_2O$,$Na_2O_2$ and $KO_2$,respectively,are

When a metal of group $1$ was dissolved in liquid ammonia,the following observations were obtained :
$(a)$ Blue solution was obtained initially.
$(b)$ On concentrating the solution,the blue colour changed to bronze colour.
How do you account for the blue colour of the solution? Give the name of the product formed on keeping the solution for some time.