ASPECt
Energy: Forms, Transformation, Transfer, and Conservation
Item RG183001: When a heat pack is uesd, energy is released because the temperature of the surroundings increases.
Heat packs are commonly used by skiers as hand warmers. A heat pack is a pouch that contains powdered iron. When a skier takes the heat pack out of the package, oxygen from the air can enter the heat pack. Once inside the heat pack, the oxygen reacts with the iron to form iron oxide (rust), and the heat pack gets warmer.
During the chemical reaction that takes place inside the heat pack, is energy being released to the surroundings or taken in from the surroundings and why?
- Energy is released because the temperature of the surroundings increases.
- Energy is released because all chemical reactions release energy.
- Energy is taken in because the temperature of the surroundings increases.
- Energy is taken in because all chemical reactions take in energy.
- Distribution of Responses
- Scale Score for Item Difficulty
(200[Easy]-800[Difficult]) - 527
- Students Responding Correctly
| Group | Correct | Total | Percent |
|---|---|---|---|
| Overall | 2121 | 7433 | 29% |
| Grades | |||
| 4–5 | 182 | 730 | 25% |
| 6–8 | 1109 | 3892 | 28% |
| 9–12 | 830 | 2811 | 30% |
| Gender | |||
| Male | 1020 | 3491 | 29% |
| Female | 1047 | 3794 | 28% |
| Primary Language | |||
| English | 1864 | 6583 | 28% |
| Other | 209 | 690 | 30% |
- Disciplinary Core Ideas
- PS1.B Some chemical reactions release energy, others store energy.