WorksheetsThermodynamics Worksheet Chemistry Printable Answers
Total questions: 27
Worksheet time: 56mins
Air flows according to differences in thermal energy. If a warm air mass is located in the northwest United States and a cold air mass is located in the southeast United States, from which direction will the winds blow?
northwest
northeast
southeast
southwest
Two liquids of different temperatures are separated by a barrier. The hot liquid is on the left side and the cold one is on the right side. Which of the following describes how the molecules move in heat flow?
Molecules from the left collide and transfer heat directly to the right side.
Molecules from the left collide and transfer heat to the barrier, which transfers heat to the right side.
Molecules from the right collide and transfer heat to the barrier, which transfers heat to the left side.
Molecules from the right collide and transfer heat directly to the right side.
Which of the following is the abbreviation for a unit of energy?
K
J
N
oC
The amount of heat needed to raise the temperature of 25 g of a substance by 15°C is 915 J. What is the specific heat of the substance?
2.05 J/g-°C
2.44 J/g-°C
2.13 J/g-°C
2.22 J/g-°C
Assuming the substances have the same mass and are heated by the same amount, which of the following substances would heat up most slowly? Use the table to identify the substance.
copper
iron
gold
aluminum
A 200 g block of a substance requires 1.84 kJ of heat to raise its temperature from 25°C to 45°C. Use the table to identify the substance.
gold
aluminum
iron
copper
According to the table, which gas would be most efficient—that is, have the greatest heat-storing ability—for transferring heat from a heat source to a heat exchanger?
oxygen
air
hydrogen
steam
It takes 23.5 kJ of heat energy to raise the temperature of 100 g of a substance by 50°C. What is the substance? Use the table to help you answer the question.
ice
ammonia
hydrogen
water
In the diagram, which letter represents the transition from liquid to gas?
E
B
C
D
You have the following equations: (refere to diagram) What is the missing ΔH?
+792 kJ
–594 kJ
–198 kJ
+198 kJ
You have a series of four chemical reactions (1 → 2 → 3 → 4). How do you calculate the ΔH2 if you know the other ΔH values?
ΔH2 = (ΔH1)(ΔH3)/(ΔH4)
ΔH2 = ΔH1 + ΔH3 – ΔH4
ΔH2 = ΔH1 + ΔH3 + ΔH4
ΔH2 = ΔH4 – (ΔH1 + ΔH3)
In a calorimeter, 100 g of ice melts at 0oC. The enthalpy of fusion of the ice is 334 J/g. How much heat was absorbed?
33.4 kJ
334 J
33.4 J
334 kJ
In which of the following thermochemical equations would the ΔH be considered a heat of solution?
2NaHCO3 (s) → Na2CO3 (s) + H2O (g) + CO2 (g), ΔH = –129 kJ
2C8H18 (l) + 25O2 (g) → 16CO2 (g) + 18H2O (l), ΔH = –5,471 kJ/mol
NH4NO3 (s) → NH4+ (aq) + NO3– (aq), ΔH = +25.7 kJ/mol
C6H6 (s) → C6H6 (l), ΔH = +9.87 kJ
Which of the following is a correctly written thermochemical equation?
2C8H18 + 25O2 → 16CO2 + 18H2O, ΔH = –5,471 kJ/mol
C3H8 (g) + O2 (g) → CO2 (g) + H2O (l), ΔH = –2,220 kJ/mol
4Fe (s) + 3O2 (g) → 2Fe2O3 (s), ΔH = –3,926 kJ
NH4Cl → NH4+ + Cl–
