The equivalent weight of phosphoric acid $(H_3PO_4)$ in the reaction $NaOH + H_3PO_4 \to NaH_2PO_4 + H_2O$ is

Which phrase would be incorrect to use?

$71 \ g$ of chlorine combines with a metal to form $111 \ g$ of its chloride. The chloride is isomorphous with $MgCl_2 \cdot 6H_2O$. The atomic weight of the metal is:

$0.45 \ g$ of an acid (mol wt. $= 90$) required $20 \ mL$ of $0.5 \ N$ $KOH$ for complete neutralization. The basicity of the acid is:

Sulphur forms the chlorides $S_2Cl_2$ and $SCl_2$. The equivalent mass of sulphur in $SCl_2$ is $....... \ g/eq$.

The atomic mass of noble gases is determined by which of the following relationships?