Based on the reaction $CH_4 + 2O_2 \to CO_2 + 2H_2O$,calculate the number of moles of oxygen required to react with $4.8 \, g$ of methane.

What volume of ammonia is required to react with $250 \ mL$ of oxygen by following the reaction at same conditions?
$4NH_3(g) + 5O_2(g) \to 4NO(g) + 6H_2O(g)$

Given the ratio of masses of nitrogen and oxygen in a particular gaseous mixture is $4: 1$. Calculate the ratio of the number of their molecules.

To neutralize completely $20 \ mL$ of $0.1 \ M$ aqueous solution of phosphorous acid $(H_3PO_3)$,the volume of $0.1 \ M$ aqueous $KOH$ solution required is .......... $mL$.

At $NTP$,the density of a gas,whose molecular weight is $45$,is ............. $g \ L^{-1}$.

What volume of $H_2$ gas in liters at $1 \, \text{atm}$ pressure and $273 \, K$ temperature is required to reduce $21.6 \, g$ of boron trichloride $(BCl_3)$ (atomic weight of $B = 10.8$) to obtain boron?