One mole of $P_4$ reacts with $8$ moles of $SOCl_2$ to give $4$ moles of $A$,$x$ moles of $SO_2$ and $2$ moles of $B$. $A$,$B$ and $x$ respectively are

If the heat of combustion of methane is $-100 \ kJ/mol$,then calculate the heat evolved when $32 \ g$ of methane reacts with $32 \ g$ of oxygen. (in $kJ$)

When $400 \ mL$ of $0.2 \ M \ H_2SO_4$ solution is mixed with $600 \ mL$ of $0.1 \ M \ NaOH$ solution,the increase in temperature of the final solution is $...... \times 10^{-2} \ K$. (Round off to the Nearest Integer).
$\left[ \text{Use } : H^{+}_{(aq)} + OH^{-}_{(aq)} \rightarrow H_2O : \Delta_{r}H = -57.1 \ kJ \ mol^{-1} \right]$
Specific heat of $H_2O = 4.18 \ J \ K^{-1} \ g^{-1}$
Density of $H_2O = 1.0 \ g \ cm^{-3}$
Assume no change in volume of solution on mixing.

For the given reaction:
$CaCO_{3} + 2HCl \to CaCl_{2} + H_{2}O + CO_{2}$
If $90 \ g$ of $CaCO_{3}$ is added to $300 \ mL$ of $HCl$ solution which contains $38.55\%$ $HCl$ by mass and has a density of $1.13 \ g \ mL^{-1}$, then which of the following options is correct?
[Given molar masses of $H$, $Cl$, $Ca$, and $O$ are $1$, $35.5$, $40$, and $16 \ g \ mol^{-1}$ respectively]

In the balanced equation of the following reaction, the ratio of $a / b$ is: $aCaCO_3 + bH_3PO_4 \rightarrow pCa_3(PO_4)_2 + qCO_2 + rH_2O$

Assign $A, B, C, D$ from the given type of reaction.
$NaBr + AgNO_3 \longrightarrow AgBr \downarrow + NaNO_3$