The value of $n$ in the molecular formula $Be_n Al_2 Si_6 O_{18}$ is

If $0.0833 \, \text{mol}$ of a carbohydrate contains $1 \, \text{g}$ of hydrogen and its empirical formula is $CH_2O$,what is its molecular formula?

$A$ compound contains $10^{-2} \%$ of phosphorus. If the atomic mass of phosphorus is $31$,the molecular mass of the compound having one phosphorus atom per molecule is :-

Calculate the mass percent of calcium,phosphorus,and oxygen in calcium phosphate $Ca_{3}(PO_{4})_{2}$.

On analysis,a certain compound was found to contain iodine and oxygen in the ratio of $254 \ g$ of iodine and $80 \ g$ of oxygen. The atomic mass of iodine is $127$ and that of oxygen is $16$. Which of the following is the formula of the compound?

In a compound,$C$,$H$,and $N$ atoms are present in $9 : 1 : 3.5$ by weight. The molecular weight of the compound is $108$. What is the molecular formula of the compound?