Potassium permanganate,on heating,gives:

Explain the biological importance of sodium and potassium.

Which of the following statement$(s)$ is (are) correct?
$(i)$ $LiF$ is less soluble in water
$(ii)$ $NaCl$ is less ionic than $CsCl$
$(iii)$ Formation of alkali metal halide is an endothermic reaction

$A$ $s$-block element $(M)$ reacts with oxygen to form an oxide of the formula $MO_{2}$. The oxide is pale yellow in colour and paramagnetic. The element $(M)$ is:

Which alkali metal emits blue colour light in a flame test?

Which of the following alkali metals has a density greater than water?