0.557 grams of a particular gunpowder will propel a 40-caliber bullet with 526 ft lbs of energy when fired. How many kJ of energy does the firing of the bullet release? (737.56 ft lbs = 1kJ)

Hydrogen 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.)

9.30 For the example of shallow water and sandy beaches, which material has a larger heat capacity or specific heat? How does a hot day at the beach provide evidence for your answer?

An aluminum kettle weighs 1.05 kg. (a) What is the heat capacity of the kettle? (b) How much heat is required to increase the temperature of this kettle from 23.0 C to 99.0 C? (c) How much heat is required to heat this kettle from 23.0 C to 99.0 C if it contains 1.25 L of water (density of 0.997 g/mL and a specific heat of 4.184 J/g C)?

Liquid hydrogen peroxide has been used as a propellant for rockets. Hydrogen peroxide decomposes into oxygen and water, giving off heat energy equal to 686 Btu per pound of propellant. What is this energy in joules per gram of hydrogen peroxide? (1 Btu = 252 cal; see also Table 1.4.)

An iron skillet weighing 1.63 kg is heated on a stove to 178C. Suppose the skillet is cooled to room temperature, 21C. How much heat energy (in joules) must be removed to affect this cooling? The specific heat of iron is 0.449 J/(gC).

Swimming Pool A swimming pool measuring 20.0m12.5m is filled with water to a depth of 3.75m. If the initial temperature is 18.4°C, how much heatmust be added to the water to raise its temperature to29.0°C? Assume that the density of water is 1.000 g/mL.

If a reaction produces 1.506 kJ of heat, which is trapped in 30.0 g of water initially at 26.5 °C in a calorimeter like that in Figure 5.12, what is the resulting temperature of the water?

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.

Thermal Interactions Part 1: In an insulated container, you mix 200. g of water at 80C with 100. g of water at 20C. After mixing, the temperature of the water is 60C. a How much did the temperature of the hot water change? How much did the temperature of the cold water change? Compare the magnitudes (positive values) of these changes. b During the mixing, how did the heat transfer occur: from hot water to cold, or from cold water to hot? c What quantity of heat was transferred from one sample to the other? d How does the quantity of heat transferred to or from the hot-water sample compare with the quantity of heat transferred to or from the cold-water sample? e Knowing these relative quantities of heat, why is the temperature change of the cold water greater than the magnitude of the temperature change of the hot water. f A sample of hot water is mixed with a sample of cold water that has twice its mass. Predict the temperature change of each of the samples. g You mix two samples of water, and one increases by 20C, while the other drops by 60C. Which of the samples has less mass? How do the masses of the two water samples compare? h A 7-g sample of hot water is mixed with a 3-g sample of cold water. How do the temperature changes of the two water samples compare? Part 2: A sample of water is heated from 10C to 50C. Can you calculate the amount of heat added to the water sample that caused this temperature change? If not, what information do you need to perform this calculation? Part 3: Two samples of water are heated from 20C to 60C. One of the samples requires twice as much heat to bring about this temperature change as the other. How do the masses of the two water samples compare? Explain your reasoning.