JAMB Chemistry Past Questions & Answers - Page 254

1,266.

When glowing splint is inserted into the mouth of a jar containing a gas, the splint is extinguished. The gas gives a white precipitate when passing into barium hydroxide. The gas is?

A.

methane

B.

hydrogen chloride

C.

hydrogen

D.

nitrogen

Correct answer is E

Co2 does not support combustion, it is used in fire extinguishers and when it is passed into a solution of barium hydroxide,  a white precipitate of barium carbonate is formed

1,267.

When a bottle of Coca-Cola is opened, bubbles of evolve. The gas is?

A.

hydrogen

B.

carbon monoxide

C.

carbon dioxide

D.

sulphur oxide

E.

chlorine

Correct answer is C

No explanation has been provided for this answer.

1,268.

An element X has 127 neutrons and 82 electrons.
Its atomic number is?

A.

209

B.

105

C.

45

D.

82

Correct answer is D

An atom that has equal number of protons and electrons is called a neutral atom

With  82 electrons, the atomic number is also 82

1,269.

Which of the following is true concerning the properties of benzene and hexane?

A.

Both undergo substitution reaction

B.

Both undergo addition reaction

C.

Both are solids

D.

Both can decolourized bromine water

Correct answer is A

Hexane and benzene can both partake in substitution reactions. 

1,270.

Terylene is synthesized from ethane- 1, 2-diol and benzene - 1, 4-dicarboxylic acid by?

A.

addition reaction

B.

condensation reaction

C.

elimination reaction

D.

substitution reaction

Correct answer is B

No explanation has been provided for this answer.