Comments on: O Levels Chemistry – Selected Exam Questions Cont’d

By: Wasiq

Wasiq — Mon, 11 Jan 2010 15:13:53 +0000

Question no 2 answer:
The increase in temperature will lead to increase in kinetic energy which ultimately leads to more effective collisions between molecules.

By: Tingwei

Tingwei — Sun, 27 Sep 2009 14:18:37 +0000

For question 2)
When the temperature increases,the kinetic energy of the particles also increase,and subsequently they’re able to collide more often.Thus,effective collision increases leading the increasing of ROR.Pls correct me, Sir..Thanks

By: S-N

S-N — Mon, 24 Aug 2009 00:19:11 +0000

Amended
In peroxide, O has a state of -1 while in H2O , it has a state of -2. In O2, it has a state of 0.

Hence, there is oxidation and reduction occuring at the same time.

By: S-N

S-N — Sat, 22 Aug 2009 18:47:44 +0000

In peroxide, O has a state of -1 while in H2O & O2 , it has a state of -2. Here, it is being reduced.

To form O2, the peroxide loses hydrogen atom, hence it is considered as oxidation .

Not very sure if it is correct, tho.

By: hina

hina — Fri, 24 Apr 2009 12:22:26 +0000

i think that since the oxidation state of hydrogen is decreasing from +4 to +1 so it is being reduced but
h2 is gaining oxygen at the same time so it is being oxidised. so i think it os right
to say that h2o2 is being oxidised and reduced at the same time.