Describe the tests for reducing sugars and starch, and outline the functions of key nutrients. Also, calculate the volume of air escaped from different soil samples.

here's the solution to questions 1 and 2:

1 (a)

i) The test described (Benedict's solution, heating, brick-red precipitate) is used to test for reducing sugars.

ii) An alternative reagent that could be used in place of Benedict's solution is Fehling's solution.

1 (b)

i) The student is likely to observe that the iodine solution turns blue-black on the piece of bread.

ii) The conclusion drawn is that starch is present in the bread.

1 (c)

i) Vitamins: Regulate body processes and protect against diseases.

ii) Proteins: Essential for growth and repair of body tissues, and form enzymes and hormones.

iii) Mineral salts: Important for bone formation, nerve function, fluid balance, and act as cofactors for enzymes.

2 (i)