When dry ammonia gas is passed over heated sodium (in absence of air),the product formed is:

$A$ metal $(A)$ on heating in nitrogen gas gives compound $(B)$. $(B)$ on treatment with $H_{2}O$ gives a colourless gas which when passed through $CuSO_{4}$ solution gives a dark blue-violet coloured solution. $(A)$ and $(B)$ respectively,are

Which of the following salts does not impart color to the flame?

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

Explain the properties of sodium carbonate.

Alkali metals lose electrons from which orbitals?