Chemistry, 11.04.2020 01:32 elricardo34

Amy is asked to determine the chemical composition of an unknown liquid sample. She determines that the sample is negative for protein, simple sugars, and lipids. However, someone else has used up all of the iodine reagent. Which scenario would allow Amy to test the unknown sample for the presence of starch

Answers: 3

Show answers

Answers

Answer from: 30352

Amy can apply the Tyndall Beam effect ,by shining a beam of light through the sample solution.

Explanation:

The chemical test for starch is add iodine solution to the tested sample which is yellow/brown and observe the color change to blue/black color. However, the physical test to distinguish simple sugars from starch is the shine a beam of light through the sample solution. Because that sample solution contained no simple sugars, then the presence of starch in the solution will be indicated by dispersal of light because the large starch molecules are enough to affect the light.

Answer from: mfweldon64

In order to test the unknown sample for the presence of starch, Amy should B. Incubate the unknown sample with amylase and then test for simple sugars.

Amylase is an enzyme that breaks starch down to sugars so if Amy incubates the substance with amylase and the substance has starch, the starch will be broken down to sugars which can then be tested for.

If there was starch, a sugar test would be positive.

Other options are wrong because:

the test is for starch so any test for proteins is wrong the Benedict's test is for sugars not starch to use potatoes to test for starch, an iodine solution is needed

In conclusion therefore, the best way to test for starch would be to incubate with amylase and then test for simple sugars.

For more information, look at link.

Options for this question include:

A. Incubate the unknown sample with pepsin and then test for proteins.

B. Incubate the unknown sample with amylase and then test for simple sugars.

C. Add a known amount of starch to the unknown sample and then run the Benedict's test.

D. Incubate the unknown sample with catalase and then test for proteins.

E. Put a small amount of the unknown sample onto a fresh potato slice and observe for color changes.

Answer from: Quest

i think it is true since you can test the answer and can use observations to complete it.

Answer from: Quest

the answer to your question is c

Another question on Chemistry

Chemistry, 21.06.2019 22:30

Which supports the idea that birds and butterflies both have wings but they do not have a common ancestor with wings? a. the wings are analogous structures that evolved differently and do not have a similar internal structure. b. the wings are homologous structures that evolved differently and do not have a similar internal structure. c. wings of birds are vestigial structures, but the wing structures of bats are not vestigial. d. wings of bats are vestigial structures, but the wing structures of birds are not vestigial

Answers: 1

Answer

Chemistry, 22.06.2019 05:00

Which position represents spring in the southern hemisphere? a) b) c) d)

Answers: 2

Answer

Chemistry, 22.06.2019 06:30

Particle model to predict what will happen if a sharp object creates a hole in the soccer ball

Answers: 2

Answer

Chemistry, 22.06.2019 14:30

In water, a strong acid will break down into its component parts. a. completely b. partly c. never in water, a weak base will break down into its component parts. a. completely b. partly c. never

Answers: 2

Answer

You know the right answer?

Amy is asked to determine the chemical composition of an unknown liquid sample. She determines that...

Questions