The approximate mass of a tritium oxide molecule is $............$ $amu$.

Calculate the molecular mass of the following:
$(i)$ $H_{2}O$
$(ii)$ $CO_{2}$
$(iii)$ $CH_{4}$

On reduction with hydrogen,$3.6 \, g$ of an oxide of a metal left $3.2 \, g$ of metal. If the equivalent weight of the metal is $32$,the simplest formula of the oxide would be:

The vapor density of a metal chloride is $77$. If the equivalent weight of the metal is $3$,what is its atomic weight?

The average molecular weight of the air which has $21 \%$ of $O_2$ and $79 \%$ of $N_2$, is

$12 \ g$ of an element reacts with $32 \ g$ of oxygen. What is the equivalent weight of the element?