M2 ,, Redox

Question 1

What is oxidation?

Answer 1

Process of electron loss, involves an increase in oxidation number
Zn —> Zn2^+ + 2e-

Question 2

What is reduction?

Answer 2

The process of electron gain, involves a decrease in oxidation
Cl2 + 2e- —> 2Cl-

Question 3

Rules for assigning oxidation numbers?

Answer 3

All uncombined elements have an oxi number of 0
Oxidation no of elements in a compound should add up to 0
Oxi number of a monoatomic ion equals to ionic charge (cl- = -1)
Polyatomic ions (CO3^2-) sum of individual oxi numbers add up to charge of ion ( c= +4 o = -2)

Question 4

Oxi numbers?

Answer 4

G1 = +1
G2 = +2
Al = +3
H = +1 except in metal hydrides where its -1
F = -1
Cl ,Br ,I = -1 except when with oxygen and Fluorine
O = -2 except in (H202) peroxides where its -1 and with F

Question 5

Redox with metals?

Answer 5

Metals generally form ions b losing electrons with increase in oxi number to form +ions

Question 6

Redox with non-metals?

Answer 6

Generally react by gaining electrons with a decrease in oxidation number to for -ions

Question 7

Oxidation with metal and acid?

Answer 7

Acid + salt —> salt + hydrogen