reducing sugars Flashcards
what is a reducing sugar
a sugar that can donate an electron to another molecule
are mono saccharides reducing or non- reducing
reducing
what are soe examples of disaccharides that are reducing sugars
maltose and lactose
what is an example of a disaccharide that is non-reducing
sucrose
what is step 1 for testing whether food has reducing sugars.
grind up the food in distilled water
what is step 2 for testing whether food has reducing sugars
filtering away the solid food particles
what is step 3 for testing whether food has reducing sugars
then place 3cm^3 of the food solution into a boiling tube
what is step 4 for testing whether food has reducing sugars
ad 3cm^3 of benedicts solution to the boiling tube
what is step 5 for testing whether food has reducing sugars
then place the boiling tube into a beaker of boiling water
why does benedicts solution make the boiling tube of food solution blue
it contains the copper ion cu2+
in step fove when we leave the boiling tube in a beaker of boiling water how long do we leave it for
5 minutes
what happens to the contents of the boiling tube if it is a reducing sugar
it stays blue
what happen if the contents of the boiling tube if it is a non reducing sugar
this then adds an electron to the copper2+ ion this now forms a copper 1 + ion and forms a red precipitate
what happens if only a very small amount of non reducing sugar is present
a very small amount of red precipitate is formed making the solution appear a green colour
what colour does the boiling tube go if more reducing sugar is present
yellow
