What volume of water is to be added to $50 \, mL$ of $4 \, N$ $NaOH$ solution to obtain a $1 \, N$ solution? $(... \, mL)$

How many grams of ethanol must be added to $1.0 \ kg$ of water to have a mole fraction of ethanol equal to $0.2$?

$A$ solution is prepared by adding $124 \ g$ of ethylene glycol (molar mass $= 62 \ g \ mol^{-1}$) to $x \ g$ of water to get a $10 \ m$ solution. What is the value of $x$ (in $g$)?

Assertion $(A)$: Molality of a solution increases with temperature.
Reason $(R)$: Molality expression does not involve any volume term.

Explain parts per million (ppm) in brief.

When equal volumes of $0.1 \ M \ AgNO_3$ and $0.2 \ M \ NaCl$ are mixed,the concentration of $NO_3^-$ in the resulting mixture will be ............. $M$.