Saleha Pervez and Shikha Goel Solutions for Chapter: Mole Concept and Stoichiometry, Exercise 7: ARCHIVES*(Last 7 Years)

The ratio between the number of molecules in $2 \mathrm{g}$ of hydrogen and $32 \mathrm{g}$ of oxygen is

A gas of mass $32\mathrm{g}$ has a volume of $20\mathrm{}\mathrm{L}$ at $\mathrm{S}\mathrm{T}\mathrm{P}$. Calculate the gram molecular weight of the gas.

How much calcium oxide is formed when $82\mathrm{g}$ of calcium nitrate is heated?
Also, find the volume of nitrogen dioxide evolved.
$2\mathrm{C}\mathrm{a}{\left({\mathrm{N}\mathrm{O}}_3\right)}_2\to 2\mathrm{C}\mathrm{a}\mathrm{O}+4{\mathrm{N}\mathrm{O}}_2+{\mathrm{O}}_2$
$\left(\mathrm{C}\mathrm{a}=40,\mathrm{}\mathrm{N}=14,\mathrm{O}=16\right)$.

A gas cylinder contains $12\times {10}^{24}$ molecules of oxygen gas. If Avogadro’s number is $6.022\times {10}^{23}$. Calculate
the mass of oxygen present in the cylinder.

A gas cylinder contains $12\times {10}^{24}$ molecules of oxygen gas. If Avogadro’s number is $6.022\times {10}^{23}$. Calculate
the volume of oxygen at $\mathrm{S}\mathrm{T}\mathrm{P}$ present in the cylinder $\left(\mathrm{O}=16\right)$.

A gaseous hydrocarbon contains $82.76\%$ of carbon. Given that its vapour density is $29$, find its molecular formula. $\left(\mathrm{C}=12,\mathrm{}\mathrm{H}=1\right)$

The equation, $4{\mathrm{NH}}_3+5{\mathrm{O}}_2\to 4\mathrm{NO}+6{\mathrm{H}}_2\mathrm{O}$, 

represents the catalytic oxidation of ammonia. If ammonia $100 {\mathrm{cm}}^3$ is used, calculate the volume of oxygen required to oxidise the ammonia completely.

Which of the following would weigh the least?
$(\mathrm{Ag}=108, \mathrm{N}=14, \mathrm{O}=16 \mathrm{and} \mathrm{C}=12)$