Aluminium reduces manganese dioxide to manganese at high temperature. The amount of aluminium required to reduce one $g \ mol$ of manganese dioxide is $.....$

Based on the equation $C_6H_{6(l)} + \frac{15}{2} O_{2(g)} \rightarrow 6CO_{2(g)} + 3H_2O_{(l)}$,the enthalpy change is $\Delta H = -3264.4 \, kJ \, mol^{-1}$. How much energy in $kJ$ is released when $7.8 \, g$ of benzene is burned in air?

When $1 \ L$ of $CO_2$ is heated with graphite,the volume of the gases collected is $1.8 \ L$. What will be the number of moles of $CO$ produced at $STP$?

How many milliliters of water must be added to $10 \, mL$ of $10 \, N \, HNO_3$ to convert it into $0.1 \, N \, HNO_3$?

$X \ g$ of $Ca$ [atomic mass $= 40$] dissolves completely in concentrated $HCl$ solution to produce $5.04 \ L$ of $H_2$ gas at $STP$. The value of $X$ is closest to

$1\, g$ of a carbonate $(M_{2}CO_{3})$ on treatment with excess $HCl$ produces $0.01186\, mol$ of $CO_{2}.$ The molar mass of $M_{2}CO_{3}$ in $g\, mol^{-1}$ is: