What is the role of an indicator? predict how the glucose test strips and iodine would react with the following foods: grape tomato summer squash orange bell pepper

The main role of an indicator is to establish the equivalence point when two substance has reached its neutralization process. The purpose of an indicator is to determine how acidic or basic the product or solution is. Indicator solutions work by actually reacting with the components of food that they test for, creating a new substance of a different color. This is a chemical reaction.If the substance that they test for is not present in the food, there will be no reaction, and therefore no color change.  The test strips will be more likely to be dark blue or black for  Grape, Tomato, Summer squash, Orange Bell pepper as they all contain starch. Color intensity may vary depending on the level of starch found in the samples. 

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