Hi there, I have a quick question which I'm really stumped on.

1. When combined with Lugol's solution (iodine), does glucose and sucrose contain starch?

I think glucose has starch but not sucrose. Is this right?

Because Glucose is the unit from which starch, cellulose and glycogen are made up, and because of its special role in biological processes, there are probably more glucose groups in Nature than any other organic group. It is extremely important in Nature as one of the main energy sources for living organisms, both in plants and animals.

sucrose does not

thanks so much for explaining!

Actually, neither glucose nor sucrose contain starch when combined with Lugol's solution. Let me explain how to determine if a substance contains starch and how to perform the Lugol's test.

Starch is a complex carbohydrate that is made up of long chains of glucose molecules. To test for the presence of starch, you can use Lugol's solution, also known as iodine solution. Lugol's solution contains iodine dissolved in potassium iodide.

Here's how you can perform the Lugol's test:

1. Take a small sample of the substance you want to test. In this case, you can take separate samples of glucose and sucrose.

2. Add a few drops of Lugol's solution to each sample.

3. Observe the color change. If the substance turns a dark blue or black color, it indicates the presence of starch. If there is no color change, it means starch is not present.

Now, let's apply the Lugol's test to glucose and sucrose:

Glucose is a monosaccharide, which means it is a simple sugar and does not contain starch. When you add Lugol's solution to glucose, you will observe that there is no color change, indicating the absence of starch.

Sucrose, on the other hand, is a disaccharide composed of glucose and fructose molecules. Like glucose, sucrose does not contain starch. Therefore, when Lugol's solution is added to sucrose, there will also be no color change.

In summary, neither glucose nor sucrose contains starch when combined with Lugol's solution.