tests for reducing and non reducing sugars and starch

Question 1

which sugar is not a reducing sugar. (also known as table sugar that you put in your tea)

Answer 1

sucrose

Question 2

what do reducing sugars do

Answer 2

they reduce other chemicals

Question 3

what is the method for reducing sugars

Answer 3

1) put the sample sugar in a test tube
2) add benadics solution (5ml)
3) place in a a boiling water bath for 3 mins

Question 4

what is a positive result for reducing sugars

Answer 4

when it turns red

Question 5

what can reducing sugars do

Answer 5

they can donate an electron to another molecule

Question 6

how would you test for a non reducing sugar

Answer 6

2)add dilute hydrocloric acid and boil for 5 mins
3)add dilute sodium hydroxide solution. test on ph paper that it is alkaline (cant do benadicts test if acidic)
4)do benadicts test
5)

Question 7

what would the acid do to the glycosilic bonds between stages 1 and 2 if a non reducing sugar was present?

Answer 7

the acid hydrolises the glycosilic bonds releasing the monosaccharides

Question 8

what is the positve result for the starch test

Answer 8

use iodine
brown/yellow——>blue/black