At $STP$,$2.8 \, L$ of a gaseous substance weighs $5.5 \, g$. If the compound contains $N$ and $O$ atoms,its molecular formula will be ..............

In an organic compound,the percentage of $C$ is $92.3 \%$. What is its empirical formula?

$2.0 \text{ g}$ of a bromo hydrocarbon $(X)$ was subjected to Carius analysis, which gave $3.36 \text{ g}$ of $AgBr$. The percentage of carbon in the compound $(X)$ is $26.7\%$. The total number of carbon atoms in the empirical formula for compound $(X)$ is . . . . . . .

Calculate the amount of aluminium present in $Al_2(SO_4)_3$ if the compound contains $4 \text{ g}$ of sulfur. [Molar mass of sulfur = $32 \text{ g/mol}$, Molar mass of $Al = 27 \text{ g/mol}$] (in $\text{ g}$)

Provide information on the percentage proportion of elements and mixtures present in Portland cement.

An organic compound is estimated through the Dumas method and is found to evolve $6$ moles of $CO_2$,$4$ moles of $H_2O$,and $1$ mole of nitrogen gas. The formula of the compound is