Oxidisers and reducers part B answer questions please?

Question

Part B: Chlorine

chlorine is a greenish-yellow poisonous gas. Its oxidisin ability makes it useful in disinfecting swimming pools and town water supplies. However, it is rarely used in its gaseous elemental form. For domestic swimming pools it is sold as a compound calcium hypochlorite, Ca(ClO)2 in bleaches it is present in aqueous solution, Cl2(aq)

Aim: to observe chlorine oxidise iodide ions

apparatus: test tube, test tube rack, access to solutions of potassium iodide, KI(aq) and chlorine water, Cl2(aq)

Method: to about 2ml of potassium iodide solution, KI (aq) *** the Cl2(aq) solution dropwise until a colour change is seen. Record what you see.

the yellow colour is due to molecular iodine, I2(aq) being formed in soluion. Cl2(aq) is changed to colourless chloride ions, Cl-

Questions:

1.a) which reactant has been oxidised?

b) write a balanced oxidation half equation

2.a)which reactant has been reduced?

b) write a balanced reduction half equation

3. develop a blanced overall equation for the reaction.

Answer 1

wouldn't you just love if someone answered this question?

Answer 2

Use OIL RIG in part b) (Oxidation Is Loss Reduction Is Gain)

1a) Iodine. Oxidation number of iodine was -2, then chlorine the oxidant 'snatched' those 2 extra electrons of iodine away because it has stronger electronegativity.

b) OIL: 2I2- (aq) --> I2 (aq) + 4e-

2a) Chlorine. ON was 0, now -2.

b) RIG: Cl2 (aq) + 4e- --> 2Cl2- (aq)

3) 2KI (aq) + Cl2 (aq) <--> 2KCl (aq) + I2 (aq)