What is the concentration of sugar $(C_{12}H_{22}O_{11})$ in $mol \ L^{-1}$ if its $20 \ g$ are dissolved in enough water to make a final volume up to $2 \ L$?

What is the value of percent atom economy if the molar mass of reactants is $36 \ u$ and the mass of the desired product is $27 \ u$ (in $\%$)?

$7.8 \ g$ of a compound having molecular formula $C_6H_6$,on reacting with $CH_3COCl / AlCl_3$ gives $8.4 \ g$ of a product which has molecular formula $C_8H_8O$. Calculate the percentage yield of the product $C_8H_8O$. (Given atomic weights of $H$,$C$ and $O$ respectively are $1$,$12$ and $16$) (in $\%$)

Equal weights of methane and oxygen are mixed in an empty container at $25\,^{\circ}C$. The fraction of the total pressure exerted by oxygen is

Sulfur trioxide is prepared by the following reactions:
$S_{8(s)} + 8O_{2(g)} \to 8SO_{2(g)}$
$2SO_{2(g)} + O_{2(g)} \to 2SO_{3(g)}$
How many grams of $SO_3$ are obtained from $1 \ mol$ of $S_8$?

Heating oxygen in the presence of a catalyst results in $15\%$ conversion to ozone. How many grams of oxygen are required to produce $33.6 \ L$ of $O_3$ at $STP$?