$56.0 \ L$ of nitrogen gas is mixed with excess of hydrogen gas and it is found that $20 \ L$ of ammonia gas is produced. The volume of unused nitrogen gas is found to be $L$.

When a mixture of $4.44 \, g$ of $CaCl_2$ and $NaCl$ is treated with a sodium carbonate solution,$Ca^{2+}$ ions precipitate as $CaCO_3$. Upon heating,this precipitate yields $0.56 \, g$ of $CaO$. Calculate the percentage of $NaCl$ in the original mixture. (Atomic mass of $Ca = 40 \, g/mol$)

$1.25 \ g$ of a solid dibasic acid is completely neutralized by $25 \ mL$ of $0.25 \ M$ $Ba(OH)_2$ solution. The molecular mass of the acid is:

On electrical decomposition of $150 \ mL$ dry and pure $O_2$,$10\%$ of $O_2$ gets changed to $O_3$. The volume of the gaseous mixture after the reaction and the volume of the remaining gas left after passing through turpentine oil will be,respectively:

Molarity of a solution containing $1 \ g$ $NaOH$ in $250 \ mL$ of solution is ...... $M$.

The number of moles of $Br_2$ produced when two moles of potassium permanganate are treated with excess potassium bromide in aqueous acid medium is