What volume of $NH_3$ gas at $STP$ would be needed to prepare $100 \ mL$ of $2.5$ molal $(2.5 \ m)$ ammonium hydroxide solution? (Assume the density of the solution is $1 \ g/mL$)

The number of moles of solute present in the solutions of $I$,$II$ and $III$ is respectively:
$I$. $500 \ mL$ of $0.2 \ M \ NaOH$
$II$. $200 \ mL$ of $0.1 \ N \ H_2SO_4$
$III$. $6 \ g$ of urea in $1 \ kg$ of water

Select the correct option based on the given figure. Symbol $T$ indicates a true statement and $F$ indicates a false statement.
Solution $P = 8 \, N$ $H_2SO_{4(aq)}$ and Solution $Q = 8 \, N$ $HNO_{3(aq)}$.
$(1)$ The number of moles of solute in solution $P$ and solution $Q$ are equal.
$(2)$ The number of gram-equivalents of solute in solution $P$ and solution $Q$ are equal.
$(3)$ The mole fraction of solvent in solution $P$ and solution $Q$ are equal.
$(4)$ The concentration of $H^+_{(aq)}$ in solution $P$ and solution $Q$ are equal.

Which of the following contain the same number of atoms?
$A$. $2 \text{ g}$ of $O_2$ gas
$B$. $4 \text{ g}$ of $SO_2$ gas
$C$. $1400 \text{ mL}$ of $O_2$ at $STP$
$D$. $0.05 \text{ L}$ of $He$ at $STP$
$E$. $0.0625 \text{ mol}$ of $H_2$ gas
Choose the correct answer from the options given below:

Substance $A_2B_{(g)}$ can undergo decomposition to form two sets of products. If the molar ratio of $A_{2(g)}$ to $A_{(g)}$ is $5 : 3$ in a set of product gases,then the energy involved in the decomposition of $1 \, \text{mole}$ of $A_2B_{(g)}$ is:
$A_2B_{(g)} \to A_{2(g)} + B_{(g)}; \Delta H^o = 40 \, \text{kJ/mol}$
$A_2B_{(g)} \to A_{(g)} + AB_{(g)}; \Delta H^o = 50 \, \text{kJ/mol}$

What is the percentage of lead in a lead pencil (in $\%$)?