Calculate the number of $Cl^{-}$ ions in $222 \ g$ anhydrous calcium chloride? (At. mass $Ca=40, Cl=35.5$)

The $\Delta H^o$ of combustion of $C_4H_{10(g)}$ is $-2650 \ kJ \ mol^{-1}$. The amount of heat evolved at constant pressure that can be obtained by burning $5.8 \ kg$ of $C_4H_{10}$ is approximately:

$A$ $250 \, mL$ solution of $Na_2CO_3$ contains $2.65 \, g$ of $Na_2CO_3$. If $10 \, mL$ of this solution is taken and diluted with distilled water up to $0.1 \, L$,what will be the molarity of the resulting solution (in $, M$)?

At $27\,^oC$,for the reaction,$N_2O_{4(g)} \to 2NO_{2(g)}$,the rate of reaction is $6 \times 10^{-3} \, atm \, min^{-1}$. Find the rate of the same reaction in terms of $mol \, L^{-1} \, min^{-1}$.

At $STP$,'$x$' $g$ of a metal hydrogen carbonate $(MHCO_3)$ (molar mass $84 \ g \ mol^{-1}$) on heating gives $CO_2$,which can completely react with $0.2 \ mol$ of $MOH$ (molar mass $40 \ g \ mol^{-1}$) to give $MHCO_3$. The value of '$x$' is

How much of $NaOH$ is required to neutralize $1500 \ cm^3$ of $0.1 \ N \ HCl$ (At. wt. of $Na = 23$)?