What is the volume (in $dm^3$) occupied by $75 \ g$ of ethane at $S$.$T$.$P$.?

What ratio by mass of $Ne$ and $CH_4$ should be mixed so that the partial pressure exerted by each gas is the same?

How many moles of potassium chlorate $(KClO_3)$ must be heated to produce $22.4 \text{ L}$ of oxygen gas at $STP$?

How many grams of dihydrogen are required to react with dinitrogen to produce $34 \ g$ of ammonia (in $g$)?

What volume (in $mL$) of gaseous $NH_3$ at $N.T.P.$ is required to be passed into $30 \, mL$ of $1 \, N \, H_2SO_4$ solution to reduce the acid strength of this solution to $0.2 \, N$?

The stoichiometric reaction of $516 \ g$ of dimethyldichlorosilane with water results in a tetrameric cyclic product $X$ in $75 \%$ yield. The weight (in $g$) of $X$ obtained is. . . . . . . [Use,molar mass $(g \ mol^{-1})$: $H=1, C=12, O=16, Si=28, Cl=35.5$]