8. Thermochemistry

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

In a coffee-cup calorimeter, 49.85g of 0.2 M HCl solution is mixed with 49.85g of 0.2 M NaOH solution, both initially at the same temperature. If the final temperature of the mixture is measured to be higher, what is the primary reason for this temperature change?

The ΔH for the solution process when solid sodium hydroxide dissolves in water is -44.4 kJ/mol. When a 12.89-g sample of NaOH (MM= 40.0 g/mol) dissolves in 250.00 g of water in a coffee-cup calorimeter, the temperature increases from 24°C to what final temperature?

Two solutions, initially at 24.69°C, are mixed in a coffee cup calorimeter. When a 200.0 mL volume of 0.100 M AgNO3 solution is mixed with a 100.0 mL sample of 0.100 M NaCl solution, the temperature in the calorimeter rises to 25.16°C. Determine the enthalpy change (ΔH) for the reaction, assuming the specific heat capacity of the solution is 4.18 J/g°C and the density is 1.00 g/mL.

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)?

Use the standard reaction enthalpies given below to determine ΔH°rxn for the following reaction: 4 S(s) + 6 O2(g) → 4 SO3(g). Given: SO2(g) → S(s) + O2(g) ΔH°rxn = +296.8 kJ, 2 SO2(g) + O2(g) → 2 SO3(g) ΔH°rxn = -198.2 kJ. What is the ΔH°rxn for the target reaction?

Given the following thermochemical equation and data, calculate the standard enthalpy of formation (ΔH⁰f) for IF(g): IF7(g) + I2(g) → IF5(g) + 2 IF(g) with ΔH⁰rxn = -89 kJ. The standard enthalpies of formation are: IF7(g) = -941 kJ/mol, IF5(g) = -840 kJ/mol, I2(g) = 62.42 kJ/mol.

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.)

What will be the change in enthalpy when 100.0 g of butane, C4H10, is burned in oxygen according to the thermochemical equation: 2 C4H10(l) + 13 O2(g) → 8 CO2(g) + 10 H2O(g) with ΔH rxn = −5271 kJ?

When 1.50 g of Ba(s) is added to 100.00 g of water in a container open to the atmosphere, the reaction shown below occurs and the temperature of the resulting solution rises from 22.00°C to 33.10°C. If the specific heat of the solution is 4.18 J/(g °C), what is the heat absorbed by the solution?

When 1.550 g of liquid hexane (C6H14) undergoes combustion in a bomb calorimeter, the temperature rises from 25.87 °C to 38.13 °C. If the heat capacity of the bomb calorimeter is 5.73 kJ/°C, what is the ΔErxn for the reaction in kJ/mol hexane?

When 3.50 g of Ba(s) is added to 100.00 g of water in a container open to the atmosphere, the reaction shown below occurs and the temperature of the resulting solution rises from 22.00°C to 47.40°C. If the specific heat of the solution is 4.18 J/(g °C), calculate the heat absorbed by the solution.

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.

When iron metal is mixed with hydrochloric acid, the following reaction occurs: 2Fe(s) + 6HCl(aq) → 2FeCl3(aq) + 3H2(g). When 1.104 g of iron is mixed with 26.023 g of HCl in a coffee cup calorimeter, the temperature rises from 25.2°C to a final temperature of 32.5°C. What is the enthalpy change (ΔH) for the reaction per mole of iron, assuming the specific heat capacity of the solution is 4.18 J/g°C and the total mass of the solution is 100.0 g?