Question

4.3 Effect of a Catalyst Test Tube Observations (2) Catalyst Present (Yes or No?) 1. Reference 2. MnO2 |3. Zn 4. fresh potato 5. boiled potato Which substance was most active as a catalyst? Q3 How does a catalyst change the rate of a reaction without affecting its equilib- rium? Q4 How do you explain the difference in catalytic activity of the fresh and boiled potatoes? B. Chemical Equilibrium: Reversible Reactions B.1 Reaction of a Hydrate Appearance Heating (1) Initial Addition of Water (2) Final Why did water droplets form at the mouth of the test tube when heated?

Answer 1

Solution:

3) A catalyst speed up the rate of reaction by decreasing the activation energy. Thus, it decreases the path of reaction without affecting equilibrium and hence causes an increase in rate of reaction.

4) Fresh potatoes exhibit higher catalytic activity than boiled potatoes because boiling of potatoes causes a destruction of enzymes, hence decreases the catalytic activity.