In potash alum, the ratio of $K^+$ and $SO_4^{2-}$ ions is

$3.0$ molal $NaOH$ solution has a density of $1.110 \, g/mL$. The molarity of the solution is

In which of the following reactions is no gas evolved on the product side? (Temperature is maintained below the boiling point of liquids formed)

$4 \ g$ equimolar mixture of $NaOH$ and $Na_{2}CO_{3}$ contains $x \ g$ of $NaOH$ and $y \ g$ of $Na_{2}CO_{3}$. The value of $x$ is $..... \ g$. (Nearest integer)

Chlorophyll extracted from the crushed green leaves was dissolved in water to make $2 \, L$ solution of $Mg$ of concentration $48 \, ppm$. The number of atoms of $Mg$ in this solution is $x \times 10^{20}$ atoms. The value of $x$ is (Nearest Integer) (Given : Atomic mass of $Mg$ is $24 \, g \, mol^{-1}$,$N_{A} = 6.02 \times 10^{23} \, mol^{-1}$)

What is the composition of the white enamel of our teeth?