8 In this question you should use changes in oxidation numbers to balance a chemical equation.
Acidified potassium dichromate(VI) solution can oxidise a solution of V2+ ions. The equation for
this reaction is shown.
a Cr2O72- + b V2+ + CH* → d Cr3+ + e VO3- + fH2O
What is the ratio a:b in the correctly balanced equation?
A 1:1
B 1:2
C 2:1
D 4:1

In chemistry, the type of an atom (what element it is) is determined by: a) the number of protons it contains in its nucleus.b) the number of neutrons it contains in its nucleus.c) the number of protons it has in a cloud around the nucleus.d) the number of neutrons it has in a cloud around the nucleus.e) the number of electrons it exchanges with its neighbors.