What amount of energy (in $KJ$) is released in the combustion of $5.8\, g$ of $C_4H_{10}\,(g)$?
$2 C_4H_{10}(g) + 13 O_2(g) \to 8 CO_2(g) + 10 H_2O(l)$; $\Delta H^o = -5756\, KJ$

The average $C-H$ bond energy is $416 \ kJ \ mol^{-1}$. Which of the following equations correctly represents the bond dissociation of $CH_4$?

The enthalpies of formation of $Al_{2}O_{3}$ and $Cr_{2}O_{3}$ are $-1596 \ kJ$ and $-1134 \ kJ$ respectively. $\Delta H$ for the reaction $2Al + Cr_{2}O_{3} \to 2Cr + Al_{2}O_{3}$ is.......$kJ$

State Hess's Law of Constant Heat Summation.

Which of the following reactions is exothermic?

The energy absorbed by each molecule $(A_2)$ of a substance is $4.4 \times 10^{-19} \ J$ and bond energy per molecule is $4.0 \times 10^{-19} \ J.$ The kinetic energy of the molecule per atom will be $...... \times 10^{-20} \ J$