4. :Reducing Agent Reduces others, but itself is being oxidized.Oxidizing Agent : Oxidizes others,but itself is being reduced.
5. Reduction & Oxidation DEFINITION OXIDATION REDUCTION#1 0XYGEN TRANSFER Gain Oxygen (+) Lose Oxygen (-)#2 HYDROGEN Lose Hydrogen (-) Gain Hydrogen(-) TRANSFER#3 ELECTRON Lose Electron Gain Electron(+) TRANSFER (-)#4 OXIDATION STATE Increase (+) Decrease (-)
6. Oxygen TransferOxidizing:Gains OReducing: Loses O
7. Oxygen Transfer Gains O₂• CuO + H2 -> Cu + H2O Loses O₂• oxidizing agent-Oxygen• reducing agent Hydrogen• Note: Oxidising & Reducing agents only refer to reactants.
8. HYDROGENTRANSFEROxidation: loses HReduction Gains H
10. Electron TransferOxidation: Loses E¯Reduction: Gains E¯
11. Electron transferOxidised ? ALUMINIUMReduced? OXYGEN
12. Oxidation stateThe oxidation state is the charge and atom of an ion in a compound.A.K.A oxidation number. OSEither a positive number(+) or a negative number(-) or zero(0) .
13. RULES EXAMPLES OXIDATION STATE1. The oxidation state of an Sodium (Na) 0elements in the uncombined state Carbon ( C ) 0(free state) is zero. Magnesium ( Mg ) 0 Oxygen (O2) 02. The oxidation state of a simple Na+ +1ion is equal to the charge on the Fe3+ +3ion. O2- -2 P3- -33.The Oxidation states of group I ALL group I and group II elements. Group 1: +1and II elements in their compoundsare fixed. Group 2: +24. The oxidation states of hydrogen H ( in H2 O ) +1and oxygen in their compound arefixed. O ( in CuO ) -2* H2O2 is the only exception wherethe O.S of oxygen is -1
14. • Oxidation occurs when the O.S of an element increases (+)• Reduction occurs when the O.S of an element decreases (-) !Oxidation and reduction always occur together
15. Example: oxidation ----increase in oxidation state (+2) (+3) 2FeCl2 (s) + Cl2 (g)  2FeCl3 • REDUCTION----decrease in oxidation state (a)Oxidation state of Iron increases from +2 in FeCl2 to +3 in 2FeCl3 . (b)Oxidation state of Chlorine decreases from 0 in Cl2 to -1 in Cl- .
16. Question• (NH4)2SO4since (NH4) has a oxidation state of +1 , (NH4)2 = +2Oxidation state of nitrogen in (NH4)2 is N2 + 8(+1)= 2(+1) N2 = +2 -8 N2 = -6 N = -3 Oxidation state of hydrogen in (NH4)2 = +1since SO4 an oxidation state of -2 ,oxidation state of sulfur in SO4 is S +4(-2)=-2 S= -2+8 S =+6 Oxidation state of oxygen in SO4 is -2