Chemical Identification of Food Molecules - Lab 4

Question 1

Chemical indicators are:

Answer 1

chemical solutions that react with particular food molecules, then they change their colors indicating the presence of particular food
molecule.

Question 2

The identification of food molecules may be:

Answer 2

Qualitative or quantitative

Question 3

Qualitative

Answer 3

detect the presence or absence of the food molecule(s)

Question 4

Quantitative

Answer 4

Detect the amount of the nutrient(s).

Question 5

The chemical tests used to detect food molecules in
this laboratory:

Answer 5

are ONLY qualitative tests.

Question 6

Molisch’s reagent

Answer 6

Detects all types of carbohydrates.

Question 7

Biuret reagent

Answer 7

Detects all types of proteins

Question 8

Emulsification test

Answer 8

Detects all types of lipids

Question 9

Molisch’s test positive test is indicated by:

Answer 9

Violet of purple ring

Question 10

Bile

Answer 10

A natural emulsifier produced by the liver

Question 11

Artificial emulsifiers

Answer 11

Ethanol, tween, liquid soap, and sodium carbonate

Question 12

Positive lipid test results in a

Answer 12

milky emulsification

Question 13

Positive protein tests results in a

Answer 13

violet color (biuret test)

Question 14

Positive Carbohydrate test results in

Answer 14

Redish-violet ring
(Molisch’s test)

Question 15

biuret solution/reagent consists of

Answer 15

Copper sulfate and sodium hydroxide