How many moles of methane are required to produce $22 \ g$ of $CO_2 \ (g)$ after combustion (in $mol$)?

What is the quantity of sugar charcoal obtained when $34.2 \ g$ of sugar is charred using the required quantity of concentrated sulphuric acid under ideal conditions (in $g$)?

What is the percentage atom economy when the formula weight of the product obtained is $70 \ u$ and the sum of the formula weights of the reactants is $140 \ u$ (in $\%$)?

Dehydration of cyclohexanol $(C_6H_{11}OH)$ to cyclohexene $(C_6H_{10})$ gives a yield of $75\%$. If $100 \ g$ of cyclohexanol is dehydrated,what is the mass of the product obtained in grams?

Some $CO_2$ gas was kept in a sealed container at a pressure of $1 \ atm$ and at $273 \ K$. This entire amount of $CO_2$ gas was later passed through an aqueous solution of $Ca(OH)_2$. The excess unreacted $Ca(OH)_2$ was later neutralized with $0.1 \ M$ of $40 \ mL$ $HCl$. If the volume of the sealed container of $CO_2$ was $x$,then $x$ is $............. \ cm^3$ $(nearest \ integer)$.
$[$Given : The entire amount of $CO_{2(g)}$ reacted with exactly half the initial amount of $Ca(OH)_2$ present in the aqueous solution.$]$

The decomposition of $H_2O_2$ produces $O_2$. If at a certain time,$48 \ g$ of $O_2$ is produced in $1 \ minute$,then the rate of formation of water at that time will be .......... $mol \ min^{-1}$.