Sodium is heated in air at $300^{\circ} C$ to form $X$. $X$ absorbs $CO_2$ and forms $Na_2CO_3$ and $Y$. Which of the following is $Y$?

The molar mass of a solute $X$ in $g \ mol^{-1}$,if its $1 \%$ solution is isotonic with a $5 \%$ solution of cane sugar (molar mass $= 342 \ g \ mol^{-1}$),is

If $A$ is a non-zero square matrix of order $n$ with $\operatorname{det}(I+A) \neq 0$ and $A^3=O$,where $I$ and $O$ are the unit and null matrices of order $n \times n$ respectively,then $(I+A)^{-1}$ is equal to

$\int \frac{x^8-9 x^2+18}{x^4-3 x^2+3} d x=$

$A$ hereditary disease which is never passed on from father to son is

The colour of the bead in the borax bead test is mainly due to the formation of: