When a student mixes 3.9537g of NaHCO3 with excess HCI in a constant pressure calorimeter the temperature of the resultant solution decreases from 19.5°C to 13.5°C. The mass of the acid is 51.02g. The heat capacity of the solution is 4.184J/g°C. Calculate the enthalpy change for the reaction assuming the calorimeter loses only a negligible amount of heat. NaHCO3(5) + HClaq) NaClag) + CO2(e) + H,O(t)

22. A 44.97−g sample of water at 72.2°C is added to a sample of water at 25.7°C in a constant-pressure calorimeter. If the final temperature of the combined water is 38.4°C and the heat capacity of the calorimeter is 26.3 J/°C, calculate the mass of the water originally in the calorimeter.

When a 4.31 g sample of liquid octane (C8H18) is burned in a bomb calorimeter, the temperature of the calorimeter rises by 27.3 °C. The heat capacity of the calorimeter, measured in a separate experiment, is 6.2 kJ/•C. The calorimeter also contains 3.00 kg of water, specific heat capacity of 4.18 J/g°C. Determine the heat of combustion of octane in units of kJ/mol octane. Enter your answer numerically and in terms of kJ/mol.

A 3.000 g sample of food was then burned in a calorimeter to determine its Calories per gram content. 50mL of water were used to determine ΔT of the reaction. Initial temperature of the water at the start of the combustion reaction was 20oC, final temperature was 99oC. Calorimeter constant for this calorimeter is 10.0J/oC. How much heat has been absorbed by the water sample?

An electrical heater adds 25.3 kJ of heat to a constant-volume calorimeter. The temperature of the calorimeter rises by 4.55 °C. When 1.75 g of methanol is burned in the same calorimeter, the temperature increases by 7.14 °C. Calculate the molar energy of combustion of methanol. kJ/mol

A 32.1 g piece of aluminum (which has a molar heat capacity of 24.03 J/°C·mol) is heated to 82.4°C and dropped into a calorimeter containing water (specific heat capacity of water is 4.18 J/g°C) initially at 22.3°C. The final temperature of the water is 25.8°C. Calculate the mass of water in the calorimeter.

The combustion of 0.1566 g benzoic acid increases the temperature of a bomb calorimeter by 2.51°C. Calculate the heat capacity of this calorimeter. (The energy released by combustion of benzoic acid is 26.42 kJ/g.) Heat capacity = kJ/°C A 0.2195-g sample of vanillin (Cg H3 O3) is then burned in the same calorimeter, and the temperature increases by 3.21°C. What is the energy of combustion per gram of vanillin? Energy = kJ/g Per mole of vanillin? Energy = kJ/mol

A 56.1 g sample of polystyrene, which has a specific heat capacity of 1.880 J-g °C-1 is put into a calorimeter (see sketch at right) that contains 250.0 g of water. The temperature of the water starts off at 24.0 °C. When the temperature of the water stops changing it's 29.8 °C. The pressure remains constant at 1 atm. Calculate the initial temperature of the polystyrene sample. Be sure your answer is rounded to the correct number of significant digits. °C thermometer. insulated container water sample. a calorimeter 區 OU Ar

A quantity of 100.0 mL of 1.0 M HCl and 100.0 mL of 1.0 M NaOH are mixed in a calorimeter. The initial temperatures of the HCl and NaOH solutions are the same at 20.0°C and the final temperature of the mixture is 27.0oC.  Calculate the heat of neutralization for the reaction in kJ/mole of NaOH.  Assume the density and specific heat of the solutions are the same as pure water and that no heat was lost to the surroundings.