Which alkali metal forms the most stable superoxide?

Most abundant salt of sodium in nature is:

Which of the following increases in magnitude as the atomic number of alkali metals in increases

Which of the following metals has stable carbonates?

On prolonged exposure to air, sodium finally changes to:

Which of the following alkali metal bicarbonates is the least soluble in water?

Sodium burns in dry air to give:

The yellow light for illumination of lamps is from:

A metal $'M'$ reacts with ${{\rm{N}}_2}$ to give a compound $'A'\left( {{M_3}N} \right).{\rm{ }}'A'$ on heating at high temperature gives back $'M'{\rm{and '}}A'$ on reacting with ${{\rm{H}}_2}{\rm{O}}$ gives a gas $B.{\rm{ }}'B'$ turns ${\rm{CuS}}{{\rm{O}}_4}$ solution blue on passing through it. $M{\rm{and}}B$ can be

A fire of lithium, sodium and potassium can be extinguished by

Which alkali metal bicarbonates does not exist as solid?