$A$ solution is prepared by adding $1 \ mole$ of ethyl alcohol in $9 \ mole$ of water. The mass percent of solute in the solution is. . . . . . . (Integer Answer)
(Given : Molar mass in $g \ mol^{-1}$ Ethyl alcohol : $46$,
water : $18$)

What is the molarity of a solution of $HCl$ which contains $49\%$ by weight of solute and whose specific gravity is $1.41$ (in $M$)?

The number of gram molecules of a substance present in unit volume is termed as

Given below are two statements: one is labelled as Assertion $A$ and the other is labelled as Reason $R$.
Assertion $A$: At $10^{\circ} C$,the density of a $5 \ M$ solution of $KCl$ is given. The solution is cooled to $-21^{\circ} C$. The molality of the solution will remain unchanged.
Reason $R$: The molality of a solution does not change with temperature as mass remains unaffected by temperature.
In the light of the above statements,choose the correct answer from the options given below:

The reason for the change in concentration of an aqueous solution with an increase in temperature is......

Which of the following is incorrect for the mole fraction $(x)$?