A quantity of 1.435 g. of naphthalene (C10H8), a pungent smelling substance used in moth repellents, was burned in a constant-volume calorimeter. Consequently, the temperature of the water rose from 20.28°C to 25.95°C. if the heat capacity of the bomb plus water was 10.17 kJ/°C, calculate the heat of combustion of naphthalene on a molar basis; that is, find the molar heat of combustion. A 0.5786 g. of unknown substance is burned in a constant-volume bomb calorimeter that has a heat capacity of 1.674 kJ/°C. After the reaction, the temperature increased by 1.432°C. Find the heat given-off by the burning of the unknown in kJ/g.

Fructose, C6H12O6(s), is a sugar closely related to glucose. A 0.755 g sample of fructose was combusted with excess oxygen in a bomb calorimeter, containing 500.0 g of water. The heat capacity of the empty calorimeter was 208 J/K. The temperature of the calorimeter and the water rose from 22.00°C to 27.12°C due to the combustion reaction, which formed CO₂(g) and liquid water. What is the energy change, AU (in kJ), for the combustion of one mole of fructose under these conditions? O +254 O-15600 -2810 +520 -804

A 2.30 g sample of ethanol, CH3CH2OH, is combusted in a bomb calorimeter. The temperature of the calorimeter increases by 4.89 K. If the heat capacity of the bomb is 663 J/K and it contains 2.57 kg of water, what is the enthalpy change per mole of ethanol combusted? The specific heat capacity of water is 4.18 J/g×K and the molar mass of ethanol is 46.07 g/mol.

A chemist wastes a delicious brownie by burning it in a bomb calorimeter.  Before burning, the brownie weighed 21.80 grams. During the combustion process in the bomb calorimeter, the heat of the calorimeter increased by 7.87 ∘C.   The known heat capacity of the calorimeter that was used was 42.73 kJ/∘C.  What is the energy content, in kJ/g, of this brownie? (Enter your answer with no units.  Since we are describing the energy content of the brownie, please ENTER THIS NUMBER AS A POSITIVE NUMBER, not a negative number!)

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.

Measurements show that the enthalpy of a mixture of gaseous reactants increases by 195.kJ during a certain chemical reaction, which is carried out at a constant pressure. Furthermore, by carefully monitoring the volume change it is determined that 69.kJ of work is done on the mixture during the reaction.  Calculate the change in energy of the gas mixture during the reaction. Be sure your answer has the correct number of significant digits. Is the reaction exothermic or endothermic?

5.00 × 10−2 mol KOH and an excess of hydrochloric acid are combined in 100.0 mL of water initially at 25.0 °C, leading to a final measured temperature of 31.1 °C. (a) What is the heat flow for the water in the calorimeter, qH2O, in Joules? (b) Assuming the calorimeter constant Ccal = 50.0 J °C , what is the heat flow for the calorimeter, qcal, in Joules? (c) What is the amount of heat given off by the reaction, qrxn, in Joules? (d) What is the molar enthalpy of the neutralization reaction (shown below) as measured in the calorimeter, ∆H◦ rxn in kilojoules per mole? H3O + (aq) + OH– (aq) → 2H2O (l)

A student is attempting to determine the heat capacity of a Styrofoam cup calorimeter by pouring hot water into a Styrofoam cup containing cold water. The student determined the mass of the cold water to be 21.2455 g and its initial temperature to be 20.36 °C. The mass of the hot water was 24.2646 g and its initial temperature as 34.54 °C. The final temperature of the water after mixing was determined to be 24.57°C. The specific heat capacity of the water is 4.184 J/(g•°C). What is the heat capacity of the Styrofoam cup calorimeter? Assume the temperature of the calorimeter is the same temperature as the cold water. 4.184 J/°C 132.5 J/°C