A solution of the enzyme amylase was added to a solution of starch and kept at 25C. The starch was broken down by hydrolysis. Explain how you would determine the rate of hydrolysis.
To determine the rate of hydrolysis in this scenario, you would need to measure the amount of starch that has been broken down over a specific period of time. Here's how you can do it:
1. Prepare several identical test tubes containing the same amount of the enzyme amylase and the same concentration of starch solution.
2. Start a timer and add a fixed volume of the amylase solution to each test tube simultaneously.
3. Mix the contents of each test tube thoroughly and place them in a water bath maintained at 25°C to maintain a constant temperature.
4. At regular intervals (e.g., every 1 minute or every 30 seconds), take small samples from each test tube.
5. Immediately add iodine solution to each sample. Iodine solution reacts with starch, resulting in a blue-black color.
6. Observe the color change in each sample and record the time at which the blue-black color disappears.
7. Repeat this procedure for each time interval until the blue-black color completely disappears in all samples.
8. Plot a graph with the time interval on the X-axis and the amount of starch remaining (indicated by the absence of the blue-black color) on the Y-axis.
9. The rate of hydrolysis can be determined by calculating the slope of the graph, as it represents the rate at which starch is being broken down by the enzyme amylase.
By measuring the changes in color as iodine interacts with the remaining starch, you can track the progress of hydrolysis over time and determine the rate at which it occurs.