2.8.2 Activation Energy Flashcards
1
Q
activation energy (Ea)
A
- of a reaction is the energy required to start the reaction
- must be supplied for the reaction to begin. The energy of activation is represented by the first increase in free energy. Once the energy of activation is supplied, the reaction proceeds on its own. The difference between the energy of the products and reactants is the net free energy gain.
2
Q
enzymes
A
- work by lowering the energy of activation
3
Q
enzyme-catalyzed reaction
A
- the energy of activation is lowered. The same net energy is released, but less energy is needed to
activate the reaction. A reaction is much more likely to proceed once the energy of activation has been lowered. If the logís activation energy was lowered, you might only have to rub it on the ground to release the energy
4
Q
Which of the following statements regarding the potential energy stored within a log is true?
A
- Potential energy is stored in the chemical bonds of the firewood
5
Q
The energy required to initiate a reaction is the
A
- activation energy
6
Q
The major effect of an enzyme in an endergonic reaction is to
A
- lower the activation energy required
7
Q
Enzymes catalyze a reaction by
A
- decreasing the amount of activation energy needed to drive the reaction
8
Q
To drive a reaction with a high positive net free energy, __________ is necessary. To speed up a reaction with a high activation energy, __________ is useful
A
- coupling with an exergonic reaction; a catalyst