What is the mass of $KClO_{3(s)}$ required to liberate $22.4 \ dm^3$ of oxygen at $STP$ during thermal decomposition (in $g$)? (Molar Mass of $KClO_{3(s)} = 122.5 \ g/mol$)

If a $100 \ mL$ solution contains $X \ g$ of $Na_2CO_3$ and its concentration is $Y \ M$,then $X$ and $Y$ are respectively ...............

For a gaseous reaction $Cl_{2(g)} + PCl_{3(g)} \to PCl_{5(g)}$. If $10 \ mL$ of $Cl_2$ completely react with $PCl_3$,then find out the produced volume of $PCl_5$ in $mL$.

$5.75 \ mg$ of sodium vapour is converted to sodium ion. If the ionisation energy of sodium is $490 \ kJ \ mol^{-1}$ and atomic weight is $23 \ g \ mol^{-1}$, the amount of energy needed for this conversion will be (in $kJ$)

Consider the reaction shown below. The percentage yield of the amide product is $......$ . (Round off to the Nearest Integer). (Given: Atomic mass: $C = 12.0 \, u, H = 1.0 \, u, N = 14.0 \, u, O = 16.0 \, u, Cl = 35.5 \, u$)
$C_6H_5COCl + (C_6H_5)_2NH \rightarrow C_6H_5CON(C_6H_5)_2 + HCl$
Given: $0.140 \, g$ of $C_6H_5COCl$ reacts with $0.388 \, g$ of $(C_6H_5)_2NH$ to produce $0.210 \, g$ of $C_6H_5CON(C_6H_5)_2$.

Formation of polyethylene from calcium carbide takes place as follows:
$CaC_2 + 2H_2O \to Ca(OH)_2 + C_2H_2$
$C_2H_2 + H_2 \to C_2H_4$
$n(C_2H_4) \to (-CH_2-CH_2-)_n$
The amount of polyethylene obtained from $64.1 \ kg$ of $CaC_2$ is......$kg$.