What is the quantity of hydrogen gas liberated when $46 \ g$ sodium reacts with excess ethanol? (Given Atomic mass of $Na = 23$)

When the same amount of zinc is treated separately with an excess of sulphuric acid and an excess of sodium hydroxide solution,the ratio of the volumes of hydrogen evolved is:

Complete combustion of $3 \ g$ of ethane gives $x \times 10^{22}$ molecules of water. The value of $x$ is ......... (Round off to the Nearest Integer). [Use: $N_{A} = 6.023 \times 10^{23} ;$ Atomic masses in $u$ $C = 12.0, O = 16.0, H = 1.0$]

How many moles of ferric alum $(NH_4)_2SO_4 \cdot Fe_2(SO_4)_3 \cdot 24H_2O$ can be made from a sample of $Fe$ containing $0.0056 \ g$ of it?

Dehydration of cyclohexanol $(C_6H_{11}OH)$ to cyclohexene $(C_6H_{10})$ gives a yield of $75\%$. If $100 \ g$ of cyclohexanol is dehydrated,what is the mass of the product obtained in grams?

If the percentage purity of an impure sample of a compound is given,then the weight of the substance required to prepare its $0.1 \, N$ solution will be: