The mass of $BaCO_3$ produced when excess $CO_2$ is bubbled through a solution of $0.205 \ mol$ $Ba(OH)_2$ is ............ $g$.

$A$ $40 \%$ $HCl$ solution has density $1.2 \ g \ mL^{-1}$. The molarity of the solution is nearly . . . . . . (in $M$)

$18 \ L$ mixture of $N_2$ and $H_2$ gives maximum $6 \ L$ of $NH_3$ at same temperature and pressure. What will be the ratio of $N_2$ and $H_2$ initially taken?

The molecular formula of a commercial resin used for exchanging ions in water softening is $C_8H_7SO_3^- Na^+$ $(Mol. \ wt. 206)$. What would be the maximum uptake of $Ca^{2+}$ ions by the resin when expressed in mole per gram resin?

Two elements $A$ and $B$ form $0.15 \ mol$ of $A_2 B$ and $AB_3$ type compounds. If $0.15 \ mol$ of both $A_2 B$ and $AB_3$ weigh equally,then the atomic weight of $A$ is $...$ times the atomic weight of $B$.

For preparing $0.05 \ N \ H_2SO_4$ solution in one litre,we need $H_2SO_4$. (in $g$)