7. Energy, Rate and Equilibrium

An energy efficient refrigerator uses 780 kWh of electrical energy per year. How many kilocalories of electricity does it use in three years?

Discuss the changes in the potential and kinetic energy of a roller-coaster ride as the roller-coaster car climbs to the top and goes down the other side.

Indicate whether each of the following statements describes potential or kinetic energy:

c. the energy in a lump of coal

Indicate whether each of the following statements describes potential or kinetic energy:

b. kicking a ball

Using the energy values for foods (see TABLE 3.7), determine each of the following (round off the answer for each food type to the tens place):

d. the grams of fat in one avocado that has 405 kcal, 13 g of carbohydrate, and 5 g of protein

Using the energy values for foods (see TABLE 3.7), determine each of the following (round off the answer for each food type to the tens place):

a. the total kilojoules in two tablespoons of crunchy peanut butter that contains 6 g of carbohydrate, 16 g of fat, and 7 g of protein

For dinner, Charles had one cup of clam chowder, which contains 16 g of carbohydrate, 12 g of fat, and 9 g of protein. How much energy, in kilocalories and kilojoules, is in the clam chowder? (Round off the answer for each food type to the tens place.)

A patient receives 3.2 L of intravenous (IV) glucose solution. If 100. mL of the solution contains 5.0 g of glucose (carbohydrate), how many kilocalories did the patient obtain from the glucose solution?

What is a catalyst, and what effect does it have on the activation energy of a reaction?

If a catalyst changes the activation energy of a forward reaction from 28.0 kcal/mol to 23.0 kcal/mol, what effect does it have on the reverse reaction?

Using energy values from TABLE 3.8, determine each of the following:

d. If expending 3500 kcal is equal to a loss of 1.0 lb, how many days will it take Charles to lose 5.0 lb?

Using energy values from TABLE 3.8, determine each of the following:

c. If Charles consumes 1800 kcal per day, he will maintain his weight. Would he lose weight on his new diet?

For the amount of exercise that Charles did for one week in part a, if expending 3500 kcal is equal to a loss of 1.0 lb, how many pounds did he lose?

For the unbalanced combustion reaction shown, 1 mol of ethanol, C₂H₅OH, releases 327 kcal (1370 kJ):

C₂H₅OH + O₂ → CO₂ + H₂O

e. If the density of ethanol is 0.789 g/mL, calculate the combustion energy of ethanol in kilocalories/milliliter and kilojoules/milliliter

A 70.0-kg person had a quarter-pound cheeseburger, french fries, and a chocolate shake.

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d. Using TABLE 3.10, determine the number of hours of running needed to burn off the kilocalories in this meal.