$120 \ g$ of urea are present in $5 \ L$ of solution. The active mass of urea is:

The number of moles of methane required to produce $11 \ g$ of $CO_{2(g)}$ after complete combustion is:
(Given molar mass of methane in $g \ mol^{-1}: 16$)

$15 \ mL$ of $N/10$ $NaOH$ solution completely neutralizes $12 \ mL$ of $H_2SO_4$ solution. The normality of $H_2SO_4$ solution will be:

The volume of $0.05 \, M$ $H_2SO_4$ required to neutralize $80 \, mL$ of $0.13 \, N$ $NaOH$ will be ...... $mL$.

When the same amount of zinc is treated separately with an excess of sulphuric acid and an excess of sodium hydroxide solution,the ratio of the volumes of hydrogen evolved is:

What amount of conc. $H_2SO_4$ solution should be used to prepare $500 \ mL$ of $0.5 \ M \ H_2SO_4$ (in $g$)? (The concentration of $H_2SO_4$ solution being used is $90\%$ and molecular mass of $H_2SO_4 = 98.079 \ g \ mol^{-1}$)