Jamb Chemistry Past Questions For Year 1995

Question 1

The number of hydrogen ions in 4.9 g of tetraoxosulphate (IV) acid is?

(S = 32, O =16, H = 1, Na = 6.02 x 10₂₃

jamb 1995

• A. 3.01 x 10₂₂
• B. 6.02 x 10₂₂
• C. 3.01 x 10₂₃
• D. 6.01 x 10₂₃

Question 2

Which of the following is a example of a chemical change?

jamb 1995

• A. Dissoultion of salt in water
• B. Rusting of iron
• C. Melting of ice
• D. Separating a mixture by distillation

Question 3

Chromatography is used to separate components of mixtures which differ in their rates of?

jamb 1995

• A. diffusion
• B. migration
• C. reaction
• D. sedimentaion

Question 4

A particle that contains 8 proton, 9 neutrons and 7 electrons could be written as?

jamb 1995

• A. O
• B. O⁺
• C. N
• D. O^-

Question 5

A liquid begins to boil when?

jamb 1995

• A. its vapour pressure is equal to the vapour pressure of its solid at the given temperature
• B. molecules start escaping from its surface
• C. its vapour pressure equals the atmosphere pressure
• D. its volume is sightly increased