a student wished to test a sample of organic material to determine whether it was sugar, a dat, or starch. If she could perform only one of the following, which would be the most revealing?
1- test for the presence of carbon and hydrogen in the sample
2- test the sample to determine the amount of amino acid present
3-burn the sample in a calorimeter
4-determine the kinds of chemical bonds present in the molecules of the sample
5- test for the presence of each substance (sugar, starch, and fat) in living organisms
but how would this be revealing if they all have the glycosidic bonds? wouldn't that just be harder to differentiate them?
To determine whether the organic material is sugar, fat, or starch, the most revealing test would be to perform number 5: test for the presence of each substance (sugar, starch, and fat) in living organisms.
Explanation:
- Testing for the presence of carbon and hydrogen in the sample (option 1) would not be conclusive as all organic materials contain carbon and hydrogen.
- Testing the sample to determine the amount of amino acid present (option 2) would not be helpful as it does not differentiate between sugar, fat, or starch.
- Burning the sample in a calorimeter (option 3) would measure the heat generated by the sample, but this test does not specifically identify the type of organic material.
- Determining the kinds of chemical bonds present in the molecules of the sample (option 4) could offer some insights, but it may not definitively identify whether the sample is sugar, fat, or starch.
Testing for the presence of each substance individually (sugar, starch, and fat) in living organisms (option 5) would give the most accurate result. This can be done by using specific tests or indicators that react specifically with each substance. These tests could include testing for the presence of reducing sugars (indicative of sugar), testing for the presence of starch using iodine solution, and testing for lipids (fats) using a Sudan IV stain method. By conducting these individual tests, the student can determine the presence or absence of each substance, providing a more conclusive identification.