Boiling point. If you boil water it changes from a liquid to a gas, which is a physical change. The rest are chemical properties because the chemical make up of an object changes.
Huh? Lol I don’t get the question
Answer:
The correct option is 3. "At pH 6.5 the enyzme is 50% active"
Explanation:
For the titratable group to be protonated and cause the enzyme to be in the active state, it needs to have gained a hydrogen cation (H+). In order for that to happen, there must be enough hydrogen cations in the environment of the enzyme, and hence, an acidic pH is required in this case.
