$A$ hydrocarbon contains $10.5 \,g$ of carbon and $1 \,g$ of hydrogen. If $2.4 \,g$ of this hydrocarbon occupies a volume of $1 \,L$ at $1 \,atm$ pressure and $127 \,^{\circ}C$ temperature,what is the molecular formula of the hydrocarbon?

$A$ gaseous compound of nitrogen and hydrogen contains $12.5\%$ (by mass) of hydrogen. The density of the compound relative to hydrogen is $16$. The molecular formula of the compound is

Find the empirical formula of the compound if $M = 68 \%$ (Atomic mass $= 34$) and the remaining $32 \%$ is oxygen:

Find the empirical formula of an organic compound if it contains $18.6 \% C$,$1.55 \% H$,and $55.04 \% Cl$. (Atomic masses: $C=12$,$H=1$,$Cl=35.5$,$O=16$)

Hemoglobin contains $0.334 \% \, Fe$ by weight. If the molecular mass of hemoglobin is approximately $67200 \, g/mol$,determine the number of iron atoms in one molecule of hemoglobin. (Atomic mass of $Fe = 56 \, g/mol$)

An organic compound having molecular mass $60$ is found to contain $C = 20\%$,$H = 6.67\%$,and $N = 46.67\%$,while the rest is oxygen. On heating,it gives $NH_3$ along with a solid residue. The solid residue gives a violet color with alkaline copper sulphate solution. The compound is: