One atomic mass unit $(amu)$ is equal to:

$4 \ g$ of copper was dissolved in concentrated nitric acid. The copper nitrate solution on strong heating gave $5 \ g$ of its oxide. The equivalent weight of copper is

If $0.228 \, g$ of silver salt of a dibasic acid gave a residue of $0.162 \, g$ of silver on ignition,then the molecular weight of the acid is:

If the molecular mass and atomic mass of sulphur are $256$ and $32$ respectively,its atomicity is:

If the equivalent mass of a metal with a valency of $+2$ is $12$,then the molar mass of its oxide is:

If the weight of $1 \ L$ of a gas is $2 \ g$,then its vapor density and molecular weight are respectively .....