Under the same conditions,how many $mL$ of $1 \ M \ KOH$ and $0.5 \ M \ H_2SO_4$ solution,respectively,when mixed to form a total volume of $100 \ mL$,produce the maximum rise in temperature?

Aqueous $HCl$ reacts with $MnO_{2(s)}$ to form $MnCl_{2(aq)}$, $Cl_{2(g)}$ and $H_{2}O_{(l)}$. What is the weight (in $g$) of $Cl_{2}$ liberated when $8.7 \ g$ of $MnO_{2(s)}$ is reacted with excess aqueous $HCl$ solution? (Given Molar mass in $g \ mol^{-1}$: $Mn=55$, $Cl=35.5$, $O=16$, $H=1$)

One litre of a gas at $STP$ weighs $1.16 \ g$. It can possibly be:

At $STP$,for complete combustion of $3\, g$ of $C_2H_6$,the required volume of $O_2$ will be - ............. $litre$.

The density of $2 \ M$ aqueous solution of $NaOH$ is $1.28 \ g \ cm^{-3}.$ The molality of the solution is $... \ m$ [Given that molecular mass of $NaOH = 40 \ g \ mol^{-1}$]

The conversion of oxygen to ozone occurs to the extent of $15\%$ only. The mass of ozone that can be prepared from $67.2 \ L$ of oxygen at $1 \ atm$ and $273 \ K$ will be ............ $g$.