JAMB Chemistry Past Questions & Answers - Page 215

1,071.

When ethene gas reacts with chlorine gas to form 1, 2-dichloroethene, the reaction is called?

A.

substitution

B.

addition

C.

polymerization

D.

hydrolysis

E.

reduction

Correct answer is B

No explanation has been provided for this answer.

1,072.

Which ONE of the following statements is true?

A.

All alkali metals salts dissolves with dissociation in water

B.

Most ionic substances are easily vaporized

C.

Ionic substances exist only as liquid

D.

Non-ionic substances are good electrolytes

E.

Nitrogen exists in a trivalent state in ammonium salts

Correct answer is A

All alkali metal salts are soluble in water.

1,073.

Element X has a total of 19 electrons and can react with oxygen to form an oxide. Which of the following statements is NOT true of the oxide of the element?

A.

When exposed to air, it slowy changes to liquid

B.

its solution in water conducts electricity

C.

Its solution in water, on evaporationm gives a white solid

D.

Its solution in water liberates hydroge when in contact with aluminium metal

E.

Its oxide, when stronlgy heated, regenerates the elements X

Correct answer is A

No explanation has been provided for this answer.

1,074.

Chlorine, bromine and iodine resemble each other in that all?

A.

dissolve in alkalis

B.

react violently with hydrogen without heating

C.

displace each other from solutions of their salts

D.

are gases

E.

are liquids

Correct answer is A

Alkali metals tend to lose one electron and form ions with a single positive charge.

They form ionic compounds (salts) in reaction with the halogens (alkali halides)

1,075.

The boiling point of water is higher than that of methanol because?

A.

water is oxide while methanol is an alcohol

B.

inter molecular forces in water are stronger than those in methanol

C.

water is an inorganic compound while methanol is organic

D.

water is an ionic compound while methanol is a covalent compound

E.

water is more reactive than methanol

Correct answer is B

No explanation has been provided for this answer.