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One method of generating electricity is by burning coal to heat water, which produces steam that drives an electric generator. To determine the rate at which coal is to be fed into the burner in this type of plant, the heat of combustion per ton of coal must be determined using a bomb calorimeter. When 1.00 g of coal is burned in a bomb calorimeter (Figure 5.17), the temperature increases by 1.48 °C. If the heat capacity of the calorimeter is 21.6 kJ/°C, determine the heat produced by combustion of a ton of coal (
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- A piece of chocolate cake contains about 400 calories. A nutritional calorie is equal to 1000 calories (thermochemical calories), which is equal to 4.184 kJ. How many 8-in-high steps must a 180-lb man climb to expend the 400 Cal from the piece of cake? See Exercise 28 for the formula for potential energy.arrow_forwardHydrogen is an ideal fuel in many respects; for example, the product of its combustion, water, is nonpolluting. The heat given off in burning hydrogen to gaseous water is 5.16 104 Btu per pound. What is this heat energy in joules per gram? (1 Btu = 252 cal; see also Table 1.4.)arrow_forwardSalicylic acid, C7H6O3, is one of the starting materials in the manufacture of aspirin. When 1.00 g of salicylic acid burns in a bomb calorimeter, the temperature of the bomb and water goes from 23.11C to 28.91C. The calorimeter and water absorb 21.9 kJ of heat. How much heat is given off when one mole of salicylic acid burns?arrow_forward
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- 9.97 Suppose that the working fluid inside an industrial refrigerator absorbs 680 J of energy for every gram of material that vaporizes in the evaporator. The refrigerator unit uses this energy flow as part of a cyclic system to keep foods cold. A new pallet of fruit with a mass of 500 kg is placed in the refrigerator. Assume that the specific heat of the fruit is the same as that of pure water because the fruit is mostly water. Describe how you would determine the mass of the working fluid that would have to be evaporated to lower the temperature of the fruit by 15C. List any information you would have to measure or look up.arrow_forwardThe standard enthalpy of formation of solid barium oxide, BaO, is 553.5 kJ/mol, and the standard enthalpy of formation of barium peroxide, BaO2, is 634.3 kJ/mol. (a) Calculate the standard enthalpy change for the following reaction. Is the reaction exothermic or endothermic? 2 BaO2(s) 2 BaO(s) + O2(g) (b) Draw an energy level diagram that shows the relationship between the enthalpy change of the decomposition of BaO2, to BaO and O2, and the enthalpies of formation of BaO2(s) and BaO2(s).arrow_forwardIn a calorimetric experiment, 6.48 g of lithium hydroxide, LiOH, was dissolved in water. The temperature of the calorimeter rose from 25.00C to 36.66C. What is H for the solution process? LiOH(s)Li(aq)+OH(aq) The heat capacity of the calorimeter and its contents is 547 J/C.arrow_forward
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