When $100 \, g$ of $CaCO_3$ reacts with $1 \, N \, HCl$,how many grams of $CO_2$ will be obtained upon completion of the reaction?

In the reaction $SO_{2(g)} + 1/2 O_{2(g)} \to SO_{3(g)}$,how many liters of air at $STP$ are required for the complete conversion of $6.4 \, g$ of $SO_2$ to $SO_3$ (in $, L$)? (Assume air contains $20 \% \, O_2$ by volume).

$A$ $1.85 \ g$ sample of an arsenic containing pesticide was chemically converted to $AsO_4^{3-}$ (atomic mass of $As = 74.9$) and titrated with $Pb^{2+}$ to form $Pb_3(AsO_4)_2$. If $20 \ mL$ of $0.1 \ M \ Pb^{2+}$ is required to reach the equivalence point,the mass percentage of arsenic in the pesticide sample is closest to

The composition of a sample of wustite is $Fe_{0.93} O_{1.00}$. The percentage of iron in the form of $Fe^{3+}$ ion is nearly:

The reaction of calcium with water is represented by the equation $Ca + 2H_2O \to Ca(OH)_2 + H_2$. What volume of $H_2$ at $STP$ would be liberated when $8 \ g$ of calcium completely reacts with water? .......... $cm^3$

The molecular weight of a gas is $45$. Its density at $STP$ is