$A$ mixture of gases contains $H_2$ and $O_2$ gases in the ratio of $1 : 4$ $(w/w)$. What is the molar ratio of the two gases in the mixture?

One litre of a gas at $STP$ weighs $1.16 \ g$. It can possibly be:

What is the mass of the precipitate formed when $50 \ mL$ of $16.9 \%$ solution of $AgNO_3$ is mixed with $50 \ mL$ of $5.8 \%$ $NaCl$ solution (in $g$)? (Atomic masses: $Ag = 107.8, N = 14, O = 16, Na = 23, Cl = 35.5$)

The formula of a gaseous hydrocarbon which requires $6$ times of its own volume of $O_{2}$ for complete oxidation and produces $4$ times its own volume of $CO_{2}$ is $C_{x}H_{y}$. The value of $y$ is $......$ .

$A$ metal chloride contains $71\%$ chlorine by mass and has a vapor density of $50$. What is the atomic mass of the metal?

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