Question

for the following reaction: CH4+2O2--->CO2+2H20

a) identify the elements oxidized and reduced

b) indicate the oxidation numbers for these elements on both sides of the equation

8. For the following reaction: (6 points) CH4 + 202 CO2 + 2H2O a) Identify the elements oxidized and reduced. b) Indicate the oxidation numbers for these elements on both sides of the equation. is the element oxidized from oxidation No. to oxidation No. is the element reduced from oxidation No. to oxidation No.

Answer 1

8.

a)

The element oxidised is C as it loses H and gains O. Loss of H and gain of O is oxidation.

The element reduced is oxygen as it gains H. Gain of H is reduction.

b)

In methane
(CH)
, the oxidation number of H is . Hence, the oxidation number of C in methane is .

In carbon dioxide
(CO2)
the oxidation number of O is . Hence, the oxidation number of C in carbon dioxide is .

C is the element oxidised from oxidation no. to oxidation no .

In dioxygen $\left ( O_2 \right )$ , the oxidation number of oxygen is as bonds between atoms of same element do not affect oxidation number.

In water
(H20)
the oxidation number of H is . Hence, the oxidation number of oxygen in water is .

Oxygen is the element reduced from oxidation no. to oxidation no .