How many moles of lead $(II)$ chloride will be formed from a reaction between $6.5 \ g$ of $PbO$ and $3.2 \ g$ of $HCl$?

The number of moles of $H_2$ required to produce $10$ moles of $NH_3$ in the following reaction is:
$a H_{2(g)} + b NO_{2(g)} \longrightarrow c NH_{3(g)} + d H_2O_{(g)}$

Assume carbon burns according to the following equation:
$2C_{(s)} + O_{2(g)} \rightarrow 2CO_{(g)}$
When $12 \ g$ of carbon is burnt in $48 \ g$ of oxygen,the volume of carbon monoxide produced is $...... \times 10^{-1} \ L$ at $STP$ [nearest integer].
[Given: Assume $CO$ as an ideal gas,molar mass of $C = 12 \ g \ mol^{-1}$,molar mass of $O = 16 \ g \ mol^{-1}$,and molar volume of an ideal gas at $STP$ = $22.7 \ L \ mol^{-1}$]

For the reaction $2Al + 3MnO \xrightarrow{\Delta} Al_2O_3 + 3Mn$; If $108 \ g$ of $Al$ and $213 \ g$ of $MnO$ are heated,then which of the following is incorrect?

$2 \ L$ of $0.2 \ M \ H_2SO_4$ is reacted with $2 \ L$ of $0.1 \ M \ NaOH$ solution. The molarity of the resulting product $Na_2SO_4$ in the solution is $X \ mM$. Find the value of $X$. (Nearest integer).

What volume of hydrogen gas at $STP$ would be liberated by the action of $50 \text{ mL}$ of $H_2SO_4$ of $50\%$ purity (density = $1.3 \text{ g mL}^{-1}$) on $20 \text{ g}$ of zinc (in $L$)? Given: Molar mass of $H, O, S, Zn$ are $1, 16, 32, 65 \text{ g mol}^{-1}$ respectively.