$A$ gas is found to contain $2.8 \ g$ of nitrogen and $3.2 \ g$ of oxygen. The simplest formula of the compound is:

The molecular formula of feldspar is

On complete combustion,$1.4 \, g$ of a hydrocarbon gave $1.8 \, g$ of water. The empirical formula of the hydrocarbon is:

Determine the empirical formula of Kevlar,used in making bulletproof vests,which contains $70.6 \% \, C, \, 4.2 \% \, H, \, 11.8 \% \, N$ and $13.4 \% \, O$.

An organic compound with a molecular weight of $60$ contains $C = 20\%$,$H = 6.67\%$,and $N = 46.67\%$,with the remainder being oxygen. Upon heating,the solid residue gives a violet color with alkaline copper sulfate solution. Identify the compound.

An organic compound has a molar mass of $108 \ g \ mol^{-1}$. The atoms $C, H,$ and $N$ are present in the weight ratio of $9 : 1 : 3.5$. What is the molecular formula of the compound?