Which of the following relation gives the value of $\mathrm{n}$? 

Empirical formula of a compound is  ${\mathrm{CH}}_{\mathrm{2}}\mathrm{O}$ and its vapour density is $30$. Molecular formula of the compound is _____

An organic compound contains $\mathrm{C} =40\%, \mathrm{H} = 6.66\%$ and rest is oxygen. The empirical formula of the compound is _______

An organic compound on analysis gave the following results: $\mathrm{C}=54.5\%, \mathrm{O} = 36.4\%, \mathrm{H}=9.1\%$. The empirical formula of the compound i s ____

An organic compound contains $\mathrm{C}=40\%, \mathrm{H}=13.33\% \mathrm{and} \mathrm{N}=46.67\%$.Its empirical formula is _______

$64 \mathrm{g}$ of an organic compound contains $24 \mathrm{g}$ of carbon, $8\mathrm{g}$ of hydrogen and the rest oxygen. The empirical formula of the compound is ______.

An organic compound having $\mathrm{C}, \mathrm{H} \text{and }\mathrm{O}$ has $13.13\% \mathrm{H}, 52.14\% \mathrm{C}$, Its molar mass is $46.068$ ${\text{g mol}}^{\text{-1}}$. What are its empirical and molecular formulae?

$0.30\mathrm{g}$ of an organic compound containing $\mathrm{C}, \mathrm{H} \mathrm{and} \mathrm{O}$ on combustion yields ${\text{0.44 g CO}}_{\text{2}}{\text{ and 0.18 g H}}_{\text{2}}\text{O}$. If one $\mathrm{mol}$ of compound weighs $60\mathrm{g}$, the molecular formula of the compound is _____.

The shapes of methane, ethene and ethyne molecules are respectively_______.