Oxidation and reduction - Jamb Chemistry Past Questions and Answers

Question 66:

• JAMB 2001

During the vulcanization of rubber, sulphur is added to

A. Break down rubber polymer
B. Lengthen the chain of rubber
C. Bind rubber molecules together
D. Act as a catalyst

Question 67:

• JAMB 2001

C₁₂H₂₂O_11(s) + H₂SO_4(aq) 12C_(s) + 11H₂O_(l) + H₂SO_4(aq)
In the reaction above, tetraoxosulphate (VI) acid function as

A. A dehydrate agent
B. An oxidizing agent
C. A reducing agent
D. A catalyst

Question 68:

• JAMB 2002

CU₂S_(s) + O_2(g) → 2CU_(s) + SO_2(g)
What is the change in the oxidation number of copper in the reaction above?

A. +1 to 0
B. 0 to +2
C. +2 to +1
D. 0 to +1

Question 69:

• JAMB 2003

If y is an oxidizing agent that reacts with a reducing agent, Z, which of the following is correct?

A. Y increases in oxidation number
B. Y becomes reduced
C. Z loses protons
D. Z gains protons

Question 70:

• JAMB 2004

Which of the following mixture of gases is likely to burn in flame

A. Neon and hydrogen
B. Nitrogen and helium
C. Helium and neon
D. Neon and nitrogen