1.2- CARBOHYDRATES- MONOSACCHARIDES

Question 1

What unusual feature do carbon atoms have?

Answer 1

very readily form bonds with other carbon atoms

Question 2

What does carbon atoms very readily forming bonds with other carbon atoms mean?

Answer 2

sequence of carbon atoms of various lengths to be built up

Question 3

What does a sequence of carbon atoms of various lengths building up form?

Answer 3

a ‘backbone’ along which other atoms can be attached

Question 4

What does a ‘backbone’ along which other atoms can be attached permit?

Answer 4

a large number of diff types and sizes of molecule, all based on carbon

Question 5

What did the versatile carbon atom cause?

Answer 5

variety of life that exists on Earth

Question 6

What are carbon-containing molecules known as?

Answer 6

organic molecules

Question 7

What are most polymers made up of?

Answer 7

carbon
hydrogen
oxygen
nitrogen

Question 8

What is the basic monomer unit in carbohydrates?

Answer 8

sugar- saccharide

Question 9

Single monomer saccharide

Answer 9

monosaccharide

Question 10

Pair of monosaccharides combined to form

Answer 10

disaccharide

Question 11

monosaccharides combined in much larger numbers

Answer 11

polysaccharides

Question 12

What are monosaccharides

Answer 12

sweet-tasting, soluble substance

Question 13

general formula of monosaccharide

Answer 13

(CH₂O)ₙ

ₙ- any number from 3-7

Question 14

E.g. of monosaccharides

Answer 14

glucose, galactose and frutcose

Question 15

What is glucose and formula?

Answer 15

hexose (6-carbon) sugar

formula- C₆H₁₂O₆

Question 16

What are all monosaccharides and some disaccharides?

Answer 16

reducing sugars

Question 17

What is reduction?

Answer 17

chemical reaction involving gain of electrons or hydrogen

Question 18

So what is a reducing sugar?

Answer 18

sugar that can donate electrons to another chemical, in this case Benedict’s reagent

Question 19

What is the test for reducing sugar

Answer 19

Benedict’s test

Question 20

What is Benedict’s solution

Answer 20

alkaline solution of copper (II) sulfate

Question 21

What happens when a reducing sugar is heated with Benedict’s reagent?

Answer 21

forms an insoluble red precipitate of copper (I) oxide

Question 22

How is the benedict test carried out?

Answer 22

1) add 2cm³ of food sample to test tube. if not in liquid form, grind up in water
2) add an equal vol of benedict’s reagent
3) heat mixture in a gently boiling water bath for 5 mins