Given the thermochemical equation 3 C(s) + 4 H₂(g) → C₃H₈(g), what is the standard enthalpy change of formation (ΔHf°) for propane, C₃H₈(g)?

The thermite reaction, Fe₂O₃ + Al → Al₂O₃ + Fe produces so much heat that the Fe product melts. This reaction is used industrially to weld metal parts under water, where a torch cannot be employed. It is also a favorite chemical demonstration in the lecture hall (on a small scale). (c) This reaction produces 852 kJ of heat per mole of Fe₂O₃ reacted. How many grams of Fe₂O₃ are needed to produce 1.00 × 10⁴ kJ of heat?

Consider the following reaction: 2 CH₃OH(g) → 2 CH₄(g) + O₂(g) ΔH = +252.8 kJ (c) For a given sample of CH₃OH, the enthalpy change during the reaction is 82.1 kJ. How many grams of methane gas are produced?