Dissolving $120 \ g$ of urea (mol. wt. $60$) in $1000 \ g$ of water gave a solution of density $1.15 \ g / mL$. The molarity of the solution is (in $M$)

$A$ solution is prepared by adding $2 \ g$ of $X$ to $1 \ mole$ of water. Mass percent of $X$ in the solution is $............. \ \%$

Which of the following statements is true?
$(1)$ $200 \ mL$ of $0.2 \ M \ NaOH$ has the same number of moles of solute as $1000 \ mL$ of $1 \ M \ NaOH$.
$(2)$ $200 \ mL$ of $1 \ M \ NaOH$ has the same number of moles as $1000 \ mL$ of $0.2 \ M \ NaOH$.
$(3)$ $100 \ mL$ of $0.2 \ M \ NaOH$ has the same number of moles as $1000 \ mL$ of $1 \ M \ NaOH$.
$(4)$ $2000 \ mL$ of $0.2 \ M \ NaOH$ has the same number of moles as $1000 \ mL$ of $1 \ M \ NaOH$.

The density of $3 \ M$ solution of $NaCl$ is $1.0 \ g \ mL^{-1}$. Molality of the solution is $...... \times 10^{-2} \ m$. (Nearest integer). Given: Molar mass of $Na$ and $Cl$ is $23$ and $35.5 \ g \ mol^{-1}$ respectively.

The mass of urea required to make $2.5 \ kg$ of $0.25 \ molal$ aqueous solution is (in $g$)

Concentrated $HCl$ is $10 \,N$. How can $1000 \,cc$ of $1 \,N \,HCl$ be prepared by dilution?