Calculate the enthalpy change (ΔH°) for the following reaction at 25 °C using the given standard enthalpies of formation (ΔfH°) in kJ/mol: 2H2(g) + O2(g) → 2H2O(l). Given: ΔfH°[H2(g)] = 0, ΔfH°[O2(g)] = 0, ΔfH°[H2O(l)] = -285.8.

A sample of steam with a mass of 0.521 g at a temperature of 100 °C condenses into an insulated container holding 4.45 g of water at 2.0 °C. For water, ΔHvap = 40.7 kJ/mol and Cwater = 4.18 J/(g·°C). Assuming that no heat is lost, what is the final temperature of the water in the container?

An 8.5 g ice cube is placed into 255 g of water. Calculate the temperature change in the water upon the complete melting of the ice. Assume that all of the energy required to melt the ice comes from the water. The enthalpy of fusion (ΔH_fusion) is 6.02 kJ/mol. What is the temperature change in the water?

What is the standard enthalpy change for the combustion of one mole of benzene (C6H6) based on the given thermochemical equation: 2 C6H6(l) + 15 O2(g) → 12 CO2(g) + 6 H2O(l) ΔHrxn° = -6534 kJ?

Calculate ΔG°rxn at 25°C for the reaction: 2CH4(g) → C2H6(g) + H2(g). Given the following standard Gibbs free energies of formation: ΔG°f(CH4) = -50.8 kJ/mol, ΔG°f(C2H6) = -32.8 kJ/mol, ΔG°f(H2) = 0 kJ/mol.

Calculate the value of ΔH° in kJ for the following reaction: 4NH3(g) + 5O2(g) → 4NO(g) + 6H2O(l), given the following standard enthalpies of formation: ΔHf°[NH3(g)] = -45.9 kJ/mol, ΔHf°[NO(g)] = 90.3 kJ/mol, ΔHf°[H2O(l)] = -285.8 kJ/mol.

Calculate ΔrH for the reaction: CH4(g) + 4 Cl2(g) → CCl4(g) + 4 HCl(g) using the given ΔfH values: CH4(g) ΔfH = -74.6 kJ/mol, CCl4(g) ΔfH = -95.7 kJ/mol, and HCl(g) ΔfH = -92.3 kJ/mol.

Choose the thermochemical equation that illustrates ΔH°f for K2SO4(s).

Consider the following generic reaction: A + 2 B → 3 C + D; ΔH = 623 kJ. What would be the value of ΔH for the following reaction: 1/3 A + 2/3 B → C + 1/3 D?