Food tests and inorganic ions.

Question 1

Inorganic ions meaning.

Answer 1

An ion that contains no more than one carbon atom.

Question 2

Magnesium formula and function.

Answer 2

Mg 2+
Chlorophyll.

Question 3

Iron formula and use.

Answer 3

Fe 2+
Haemoglobin.

Question 4

Phosphate formula and use.

Answer 4

PO4(3-)
Nucleic acids
Phospholipids.

Question 5

Calcium formula and use.

Answer 5

Ca 2+
Strengthening bones and teeth (animals)
Strengthening cell walls (plants).

Question 6

Test for proteins.

Answer 6

Biuret test
Blue=negative
Positive=purple/violet.

Question 7

Test for starch.

Answer 7

Iodine solution
Negative=red/brown
Positive=blue/black.

Question 8

Test for reducing sugars.

Answer 8

Benedict’s reagent
Negative=blue
Positive=change along the colour spectrum
Semi-quantitative-further along colour spectrum=more sugars present.

Question 9

Test for non-reducing sugars.

Answer 9

Same as reducing sugars
but must be hydrolysed by boiling in HCL first.

Question 10

Meaning of reducing sugars.

Answer 10

Sugars which reduce copper II sulphate.