Thermochemistry Review Activity

The specific heat of aluminum is 0.90 J/g·°C. How much energy is required to raise the temperature of 10 grams of aluminum from 10°C to 20°C?
1. 90 joules
2. 0.009 joules
3. 111 joules
4. 100.9 joules
A 100 gram sample of a metal undergoes a temperature change from 20°C to 50° after absorbing 1500 J of heat. What is the specific heat of the metal?
1. 0.5 J/g·°C
2. 2 J/g·°C
3. 4.5 x 10⁶ J/g·°C
4. 0.25 J/g·°C
How many joules of heat energy are required to raise the temperature of 20 grams of water by 50°C?
1. 4180 joules
2. 239.2 joules
3. 0.00418 joules
4. 19.7 joules
What energy change has occured occurred when 500 grams of water cools from 35°C to 25°C?
1. -20 900 joules
2. 20 900 joules
3. -1196 joules
4. 11.96 joules
How many joules are required to vaporize 10 grams of water at its boiling point?
1. 22 600 joules
2. 226 joules
3. 0.0044 joules
4. 2270 joules
How much energy must be removed from 2 grams of water at 0°C to convert the water to ice?
1. 668 joules
2. 167 joules
3. 0.00599 joules
4. 336 joules
What mass of ice at 0°C can be melted by the addition of 1670 joules of heat?
1. 5 grams
2. 0.2 grams
3. 8350 grams
4. 1670 grams
How many grams of water at 100°C can be converted to steam by the addition of 565 joules of heat?
1. 0.25 grams
2. 4 grams
3. 56 500 grams
4. 1 276 900 joules
A 100 gram piece of brass at a temperature of 100°C is dropped into 100 grams of water that has a temperature of 20°C. Which of the following describes what happens next?
1. They come to equilibrium at a temperature above 60°C, because the metal has a higher specific heat than does the water.
2. They come to equilibrium at a temperature above 60°C, because the metal has a lower specific heat than does the water.
3. They come to equilibrium at a temperature below 60°C, because the metal has a higher specific heat than does the water.
4. They come to equilibrium at a temperature below 60°C, because the metal has a lower specific heat than does the water.
When a piece of gold (specific heat 0.13 J/g·°C) and a piece of iron (specific heat 0.46 J/g·°C) each absorb an equal amount of heat
1. the gold will end up with the higher final temperature
2. the iron will end up with the higher final temperature
3. they will end up at the same final temperature
Which of the following phase changes involve the addition (absorption) of heat?
1. condensation
2. vaporization
3. freezing
4. melting
Which of the following phase changes involve the removal (release) of heat?
1. condensation
2. vaporization
3. freezing
4. melting
When you mixed magnesium with hydrochloric acid in the lab, the reaction got warmer. This indicates that
1. the reaction is exothermic, because energy was released
2. the reaction is endothermic, because energy was released
3. the reaction is exothermic, because energy was absorbed
4. the reaction is endothermic, because energy was absorbed
When you mixed baking soda with citric acid in the lab, the reaction got colder. This indicates that
1. the reaction is exothermic, because energy was released
2. the reaction is endothermic, because energy was released
3. the reaction is exothermic, because energy was absorbed
4. the reaction is endothermic, because energy was absorbed
In an exothermic reaction,
1. the energy content of the reactants is greater than the energy content of the products
2. the energy content of the reactants is less than the energy content of the products
3. the energy content of the reactants is the same as the energy content of the products
In an endothermic reaction,
1. the energy content of the reactants is greater than the energy content of the products
2. the energy content of the reactants is less than the energy content of the products
3. the energy content of the reactants is the same as the energy content of the products
In the diagram above, the energy content of the reactants is
1. 80 kilojoules
2. 160 kilojoules
3. 240 kilojoules
In the diagram above, the energy content of the products is
1. 80 kilojoules
2. 160 kilojoules
3. 240 kilojoules
In the diagram above, the activation energy (E_a) would be calculated by doing which of the following?
1. 240 kilojoules - 160 kilojoules = 80 kilojoules
2. 240 kilojoules - 80 kilojoules = 160 kilojoules
3. 80 kilojoules + 160 kilojoules = 240 kilojoules
4. 160 kilojoules - 80 kilojoules = 80 kilojoules
In the diagram above, the heat of reaction (ΔH) would be calculated by doing which of the following?
1. 240 kilojoules - 160 kilojoules = 80 kilojoules
2. 240 kilojoules - 80 kilojoules = 160 kilojoules
3. 240 kilojoules + 160 kilojoules = 240 kilojoules
4. 160 kilojoules - 80 kilojoules = 80 kilojoules
In the diagram above, the energy content of the products
1. is the same as the energy content of the reactants
2. is the greater than the energy content of the reactants
3. is less than the energy content of the reactants
The diagram above depicts a reaction that is
1. endothermic
2. exothermic
3. isothermic