$A$ solution contains $1.2046 \times 10^{24}$ hydrochloric acid molecules in one $dm^3$ of the solution. The strength of the solution is .......... $N$.

$23 \ g$ of $Na$ will react with methyl alcohol to give:

$A$ sample of nitric acid has a density of $1.41 \ g \ mL^{-1}$ and the mass percentage of nitric acid is $69 \%$. Calculate the concentration of nitric acid in the sample in moles per liter. (in $M$)

The yield of each step as actually carried out in the laboratory is given in the reaction scheme below. Calculate the overall percentage yield of the reaction.
$Me_3C-CO-CH_3$ $\xrightarrow{58\% (A)} Me_3C-CO-CH_2Br$ $\xrightarrow{54\% (B)} Me_3C-CH(OH)-CH_2Br$ $\xrightarrow{68\% (C)} Me_3C-CH(O)CH_2$

$10 \ mol$ of a mixture of hydrogen and oxygen gases at a pressure of $1 \ atm$ at constant volume and temperature,react to form $3.6 \ g$ of liquid water. The pressure of the resulting mixture will be closest to $..... \ atm$

When $1 \ L$ of $CO_2$ is heated with graphite,the volume of the gases collected is $1.8 \ L$. What will be the number of moles of $CO$ produced at $STP$?