8. Thermochemistry

How much heat is absorbed when 30.00 g of C(s) reacts in the presence of excess SO2(g) to produce CS2(l) and CO(g) according to the following chemical equation? 5 C(s) + 2 SO2(g) → CS2(l) + 4 CO(g), ΔH = 239.9 kJ

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.

Mothballs are composed primarily of the hydrocarbon naphthalene (C10H8). When 0.820 g of naphthalene burns in a bomb calorimeter, the temperature rises from 25.10 °C to 31.56 °C. Find ΔErxn for the combustion of naphthalene given that the heat capacity of the calorimeter is 5.50 kJ/°C.

A 100 mL sample of 0.3 M NaOH is mixed with a 100 mL sample of 0.3 M HCl in a coffee cup calorimeter. If both solutions were initially at 35°C and the temperature of the resulting solution was recorded as 37°C, determine ΔH_rxn (in units of kJ/mol NaOH) for the reaction.

Using the provided table and the equation below, determine the heat of formation (in kJ/mol) for KClO₃. 2 KClO₃ (s) → 2 KClO₂ (s) + O₂ (g) ΔH° = 296.2 kJ/mol

What is the enthalpy change (in kJ) of a chemical reaction that raises the temperature of 250.0 mL of solution having a density of 1.25 g/mL by 3.33 °C? (The specific heat of the solution is 3.74 J/g-K.)

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.

When 8.00 g of Ba (s) is added to 100.00 g of water in a container open to the atmosphere, the reaction shown occurs and the temperature of the resulting solution rises from 22.0°C to 77.62°C. If the specific heat of the solution is 4.18 J/(g°C), calculate ΔH for the reaction. Assume no heat is lost to the surroundings.

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?

Sodium metal reacts with water to produce hydrogen gas and sodium hydroxide according to the chemical equation shown below. When 0.025 mol of Na is added to 100.00 g of water, the temperature of the resulting solution rises from 25.00°C to 35.75°C. If the specific heat capacity of water is 4.18 J/g°C, what is the enthalpy change (ΔH) for the reaction per mole of Na?

Given the thermochemical equation CH4(g) + 2O2(g) → CO2(g) + 2H2O(g) with ΔH°rxn = -802.3 kJ, what minimum mass of CH4 is required to heat 85.0 g of water by 30.0 °C, assuming 100% heating efficiency? (For water, Cs = 4.18 J/g°C).

What final temperature will 120 g of benzene at 7°C have after it absorbs 2.20 kJ of heat? The specific heat capacity (Cp) of benzene is 1.74 J/g°C.

Use the standard reaction enthalpies given below to determine ΔH°rxn for the following reaction: 4 NO(g) + 2 O2(g) → 4 NO2(g). Given: N2(g) + O2(g) → 2 NO(g), ΔH°rxn = +183 kJ. What is the ΔH°rxn for the reaction 4 NO(g) + 2 O2(g) → 4 NO2(g)?

What is the change in enthalpy in kilojoules when 3.20 mol of Mg is completely reacted according to this reaction: 2Mg(s) + O2(g) -> 2MgO(s)? ΔH = -1204 kJ

Which of the following reactions correctly represents the heat of hydration for the dissolution of gaseous sodium ions (Na+) in water?