Explain why alkali and alkaline earth metals cannot be obtained by chemical reduction methods?

Assertion $A$: Alkali metals impart characteristic colors to the flame in the flame test.
Reason $R$: They have very low ionization enthalpy.

$Mg$ forms $Mg^{2+}$ but not $Mg^+$. The reason is ...

Which of the following $s$-block elements forms a nitride directly by reacting with $N_2$?

The alkali metals which form normal oxide,peroxide,as well as superoxides 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.