I need a lab report made with a \"Purpose\" statement, Procedure, hypothesis, an

Question

I need a lab report made with a "Purpose" statement, Procedure, hypothesis, and results statement. The experiment is below. Thanks

Chemical Composition of Cells: Experiment Instructions (Lab Report) LEARNING GOALS By the end of this unit, you should be able to do the following: 1. Describe the difference between organic and inorganic chemicals. 2. Relate oxygen content of a chemical to whether it is hydrophilic or hydrophobic. 3. Explain the relationship between starch, fiber, and complex carbohydrates and how they relate to glucose, sugar, and simple sugars 4. Describe how to use iodine, Benedict, and Biuret tests to identify starch, simple sugars, and protein respectively. 5. Describe the color of a positive reaction and a negative reaction for iodine, Benedict, and Biuret tests. 6. Describe how an emulsifier changes the mixing of oil and water. 7. Identify the Independent, Dependent, and Control Variables in your experiment. MATERIALS NEEDED 1 bottle of iodine (Get "Iodine Tincture" or Betadine antiseptic in the pharmacy section. DO NOT use decolorized iodine.) l bottle of blue or green food coloring 1 small potato 1 small onion 1 leaf of lettuce 1 stick of butter egg yolk

Explanation / Answer

Purpose : To test the presence of starch in the given food samples.

Procedure : Iodine test is performed.

Small amount of each food samples is taken in a beaker

10ml of distilled water is added to the samples and thoroughly ground.

A drop of iodine is added to each beaker cointainig samples

Change in colour is observed.Colour change of the samples to blue black indicates the presence of starch.

Hypothesis :

Water and corn starch serves as posoitive and negative control

When iodine was added to the samples of lettuce, vegetable oil, onion, no colour change was observed. Whereas when iodine was added to sugar, potato, peas, yams and pumpkin, significant change in colour to blue black was observed.

Results

+ presence of starch, - absence of starch

The results were compared with the positive and negative control. From the above table it is clearly reported that the starchy vegetables like roots and bulbs that include potato, yam and other vegetables like peas and pumpkin showed a change in colour to blue black indicating the presence of starch. Food sample like sugar did not show any colour change though it is a carbohydrate. Simple sugars do not contain starch and thus no colour change was observed. Other samples like vegetable oil and onion were also negative showing the absence of starch.

Food samples Presence of starch Water (negative control) - Corn starch (positive control) + Lettuce - Sugar - vegetable oil - Potato + Onion - Peas + Yam + Pumpkin +

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