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

Which elements of group-$1$ and group-$2$ differ from the other elements of the same group?

Lithium shows diagonal relationship with element $X$ and aluminum with $Y$. $X$ and $Y$ respectively are

Identify the correct statements about alkali metals.
$A$. The order of standard reduction potential $(M^{+} \mid M)$ for alkali metal ions is $Na > Rb > Li$.
$B$. $CsI$ is highly soluble in water.
$C$. Lithium carbonate is highly stable to heat.
$D$. Potassium dissolved in concentrated liquid ammonia is blue in colour and paramagnetic.
$E$. All the alkali metal hydrides are ionic solids.
Choose the correct answer from the options given below.

$NaHCO_3$ can be manufactured by Solvay's process but $K_2CO_3$ cannot be prepared because

What is the use of amalgam alloys?