(a(i))[1]
Deduce the percentage by mass contributed by the remaining elements in the biosphere.
(a(ii))[1]
Which metallic element occurs in the oceans at the greatest percentage by mass?
(a(iii))[2]
Give two major differences in the percentage by mass of the elements in the oceans and the biosphere.
(b(i))[1]
Name the other product formed during respiration.
(b(ii))[2]
Describe a chemical test that can be used for water. test ............... observations ...............