$24 \ g$ of $Mg$ metal reacts with water. How many moles of $H_2$ will be liberated? ............. $mol$

How many grams of bromine are required to react with $21 \ g$ of $C_3H_6$? (Atomic mass of $Br = 80$)

For the reaction $Fe_{2}O_{3} + 3 CO \longrightarrow 2 Fe + 3 CO_{2}$,the volume of carbon monoxide required to reduce one mole of ferric oxide is (in $dm^{3}$)

The vapour density of a certain gas is $16$. What is the volume occupied by $8 \ g$ of gas at $STP$ assuming ideal behaviour (in $dm^3$)?

The active mass of $64 \ g$ of $HI$ in a $2 \ L$ flask is......

$A$ hydrocarbon containing $C$ and $H$ has $92.3 \% C$. When $39 \ g$ of hydrocarbon was completely burnt in $O_2$,$x$ moles of water and $y$ moles of $CO_2$ were formed. $x$ moles of water is sufficient to liberate $0.75$ moles of $H_2$ with $Na$ metal. What is the weight (in $g$) of oxygen consumed? $(C=12 \ u; H=1 \ u)$