For the combustion reaction of $1 \, mol$ of hydrocarbon $C_xH_{2y}$,the number of moles of $O_2$ required will be............

For the complete combustion of $1 \, mol$ of a compound with the molecular formula $C_xH_yO_z$,the number of moles of $O_2$ required is:

$5.85 \, g$ of $NaCl$ is dissolved in $1 \, L$ of pure water. Calculate the total number of ions in $1 \, mL$ of this solution.

What is the weight of carbon in $kg$ required to produce $270 \ kg$ of aluminum from bauxite by the Hall-Heroult process?

The exact volumes of $1\, M\, NaOH$ solution required to neutralize $50\, mL$ of $1\, M\, H_3PO_3$ solution and $100\, mL$ of $2\, M\, H_3PO_2$ solution,respectively,are:

$7.5 \ g$ of a gas occupies $5.8 \ L$ of volume at $STP$. The gas is