MEGA
Energy Changes
Some chemical reactions release energy into the surroundings, whereas other chemical reactions take in energy fr…
Item EC016003: The energy released by a reaction could be used for another chemical reaction, but that reaction would have to require an input of less energy.
Scientists determined that a particular chemical reaction releases 213 kcal (891 kJ) of energy for every mole of product produced [A kilocalorie (kcal) and a kilojoule (kJ) are units of energy and a mole is a very large quantity of molecules]. What could the energy that is released by this reaction be used for?
- The energy released by this reaction could only be used to reverse the chemical reaction and turn the products back into reactants.
- The energy released by this reaction could be used for another chemical reaction that requires an input of 213 kcal (891 kJ) of energy.
- The energy released by this reaction could be used for another chemical reaction, but that reaction would have to require an input of less than 213 kcal (891 kJ) of energy.
- All of the energy released by this reaction would be released into the surrounding environment and could not be used for any other chemical reactions
Pre-Test
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 115 |
6–8 n = 0 |
9–12 n = 98 |
Male n = 56 |
Female n = 44 |
English n = 89 |
Other n = 5 |
||
| A. | The energy released by this reaction could only be used to reverse the chemical reaction and turn the products back into reactants. | 25% | NAN% | 27% | 30% | 20% | 27% | 0% |
| B. | The energy released by this reaction could be used for another chemical reaction that requires an input of 213 kcal (891 kJ) of energy. | 21% | NAN% | 20% | 25% | 18% | 20% | 20% |
| C. | The energy released by this reaction could be used for another chemical reaction, but that reaction would have to require an input of less than 213 kcal (891 kJ) of energy. | 36% | NAN% | 33% | 23% | 48% | 33% | 80% |
| D. | All of the energy released by this reaction would be released into the surrounding environment and could not be used for any other chemical reactions | 18% | NAN% | 20% | 21% | 14% | 20% | 0% |
Post-Test
Answer Choice |
Overall |
Grades |
Gender |
Primary Language |
||||
|---|---|---|---|---|---|---|---|---|
| n = 143 |
6–8 n = 0 |
9–12 n = 132 |
Male n = 71 |
Female n = 58 |
English n = 120 |
Other n = 10 |
||
| A. | The energy released by this reaction could only be used to reverse the chemical reaction and turn the products back into reactants. | 17% | NAN% | 17% | 15% | 17% | 16% | 20% |
| B. | The energy released by this reaction could be used for another chemical reaction that requires an input of 213 kcal (891 kJ) of energy. | 29% | NAN% | 28% | 34% | 21% | 28% | 30% |
| C. | The energy released by this reaction could be used for another chemical reaction, but that reaction would have to require an input of less than 213 kcal (891 kJ) of energy. | 36% | NAN% | 39% | 28% | 50% | 39% | 40% |
| D. | All of the energy released by this reaction would be released into the surrounding environment and could not be used for any other chemical reactions | 17% | NAN% | 17% | 23% | 12% | 18% | 10% |