Who is called the father of chemistry?

Which of the following substances represents calcium chlorite?

$A$ mixture of hydrogen and oxygen contains $20\%$ by weight of hydrogen. Find the total number of molecules per gram of the mixture.

You are given $500 \ mL$ of $2 \ N \ HCl$ and $500 \ mL$ of $5 \ N \ HCl$. What will be the maximum volume of $3 \ M \ HCl$ that you can make from these two solutions? .............. $mL$

What quantity (in $mL$) of a $45\%$ acid solution of a mono-protic strong acid must be mixed with a $20\%$ solution of the same acid to produce $800 \ mL$ of a $29.875\%$ acid solution?

The normality of $H_{2}SO_{4}$ in the solution obtained on mixing $100 \ mL$ of $0.1 \ M \ H_{2}SO_{4}$ with $50 \ mL$ of $0.1 \ M \ NaOH$ is $\times 10^{-1} \ N$. (Nearest Integer)