The molecular formula of a commercial resin used for exchanging ions in water softening is $C_8H_7SO_3^- Na^+$ $(Mol. \ wt. 206)$. What would be the maximum uptake of $Ca^{2+}$ ions by the resin when expressed in mole per gram resin?

What is obtained when one mole of calcium phosphide is reacted with excess water?

Excess of carbon dioxide is passed through $50 \ mL$ of $0.5 \ M$ calcium hydroxide solution. After the completion of the reaction,the solution was evaporated to dryness. The solid calcium carbonate was completely neutralized with $0.1 \ N$ hydrochloric acid. The volume of hydrochloric acid required is (Atomic mass of calcium $= 40$ ) (in $cm^{3}$)

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

What will be the amount of $MgCl_2$ produced when $17 \ g$ of $HCl$ is reacted with an excess of $MgO$ in the following reaction?
$MgO + 2HCl \longrightarrow MgCl_2 + H_2O$

What is the percent atom economy if the formula weight of reactants and the formula weight of products are $45 \ u$ and $35 \ u$ respectively (in $\%$)?