H2O (l) → H2O (g); ΔH = +44.0 kJ/mol
8. Thermochemistry
Constant-Volume Calorimetry
- Multiple ChoiceWhen water evaporates from a beaker at 25℃, 44.0 kJ/mol of heat is required. How much heat is required when 10.0 g of water completely evaporates?
- Open Question
A sample of 0.562 g of carbon is burned in oxygen in a bomb calorimeter, producing carbon dioxide. assume both the reactants and products are under standard state conditions, and that the heat released is directly proportional to the enthalpy of combustion of graphite. The temperature of the calorimeter increases from 26.74 °C to 27.93 °C. What is the heat capacity of the calorimeter and its contents?
- Open Question
When a 0.740-g sample of trinitrotoluene (tnt), C7H5N2O6, is burned in a bomb calorimeter, the temperature increases from 23.4 °C to 26.9 °C. The heat capacity of the calorimeter is 534 J/°C, and it contains 675 ml of water. How much heat was produced by the combustion of the tnt sample?
- Open Question
Calculate the heat capacity of a calorimeter if the combustion of 5.000g of benzoic acid
- Open Question
Calculate the heat capacity of the calorimeter if the combustion of 5.000g of benzoic acid
- Open Question
Compare the calorimeter that you built to a bomb calorimeter. How are they similar and different?
- Open Question
What is the approximate energy density (in mj/kg) of olive oil?
- Multiple ChoiceWhat is the specific heat capacity of the bomb calorimeter if burning 100.0 moles of sulfamic acid results in a temperature increase of 4.57°C, given that the ΔErn for the combustion of 1 mole of sulfamic acid is -686.2 kJ?
- Multiple ChoiceA 2.49 g sample of aniline (C6H5NH2, molar mass = 93.13 g/mol) was combusted in a bomb calorimeter with a heat capacity of 4.25 kJ/°C. If the temperature rose from 29.5 °C to 69.8 °C, determine the value of ΔH°comb for aniline.
- Multiple ChoiceA 21.8 g sample of ethanol (C2H5OH) is burned in a bomb calorimeter, causing the temperature to rise from 25.0°C to 62.3°C. Given that the molar mass of ethanol is 46.07 g/mol, what is the heat capacity of the calorimeter?
- Multiple ChoiceA 6.55 g sample of aniline (C6H5NH2, molar mass = 93.13 g/mol) was combusted in a bomb calorimeter with a heat capacity of 14.25 kJ/°C. If the initial temperature was 32.9°C and the combustion of aniline releases 30.0 kJ/g, what is the final temperature of the calorimeter?
- Multiple ChoiceA 6.55 g sample of aniline (C6H5NH2, molar mass = 93.13 g/mol) was combusted in a bomb calorimeter. If the temperature rose by 32.9°C, use the information below to determine the heat capacity of the calorimeter. The balanced reaction is: 4 C6H5NH2(l) + 35 O2(g) → 24 CO2(g) + 14 H2O(g) + 4 N2(g). Given that the standard enthalpy of combustion for aniline is -3170 kJ/mol, what is the heat capacity of the calorimeter?
- Multiple ChoiceA calorimeter is to be calibrated: 72.55 mL of water at 71.6 °C is added to a calorimeter containing 58.85 mL of water at 22.4 °C. After stirring and waiting for the system to equilibrate, the final temperature reached 47.3 °C. Determine the calorimeter constant, given that the specific heat capacity of water is 4.18 J/g°C.
- Multiple ChoiceIn a constant-volume calorimetry experiment using a bomb calorimeter, what thermodynamic quantity is directly measured?
- Multiple ChoiceMothballs 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. The heat capacity of the calorimeter is 5.11 kJ/°C. What is the value of ΔErxn in kJ/mol?