To find the initial rate of the enzymatic reaction, you need to consider the change in product formed over time. The initial rate is the rate of reaction at the beginning of the reaction, when time is equal to zero.
Looking at the given data, you can see that at 0 seconds, no product was formed. At 10 seconds, 0.25 mg of product was formed. So, the change in product from 0 to 10 seconds is 0.25 mg. The time interval is 10 seconds. Therefore, the initial rate can be calculated as:
Initial Rate = Change in Product formed / Time Interval
= (0.25 mg - 0.0 mg) / 10 seconds
= 0.25 mg / 10 seconds
= 0.025 mg/s
The rate after 50 seconds can be determined in a similar way. At 50 seconds, 0.85 mg of product was formed. So, the change in product from 0 to 50 seconds is 0.85 mg. The time interval is 50 seconds. Therefore, the rate at 50 seconds can be calculated as:
Rate at 50 seconds = Change in Product formed / Time Interval
= (0.85 mg - 0.0 mg) / 50 seconds
= 0.85 mg / 50 seconds
= 0.017 mg/s
If you were to heat the enzyme for 10 minutes at 100 degrees Celsius before repeating the experiment, it would likely denature the enzyme. Enzymes have specific temperature optima at which they function best. Heating the enzyme above its optimal temperature can cause the enzyme's structure to change, leading to a loss of activity or denaturation. This would result in a decrease or loss of enzyme activity, affecting the rate of the reaction.
Yes, altering the substrate concentration can affect the rate of reaction. Generally, increasing the substrate concentration will lead to an increase in the rate of the enzymatic reaction until the enzyme reaches saturation, where further increases in substrate concentration will not significantly increase the rate. This is because more substrate molecules will be available for the enzyme to bind with, allowing more reactions to occur per unit of time.
Changing the pH can also affect the rate of the enzymatic reaction. Enzymes have an optimum pH at which they function most effectively. Deviating from this optimum pH can disrupt the enzyme's structure, alter the ionic charges, or affect the active site's shape, leading to a decrease in enzyme activity. Therefore, changing the pH external to the optimal range can either decrease or completely inhibit the rate of the reaction.