Chemistry questions and answers

Chemistry Questions and Answers

Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.

3,496.

The alkyl group can be represented by the general formula

A.

CnH2n+1

B.

CnH2n

C.

CnH2n+2

D.

CnH2n-2

Correct answer is A

No explanation has been provided for this answer.

3,497.

Oxyacetylene flame is used for iron-welding because it

A.

Makes the iron metals solidify very quickly

B.

Combines with oxygen to give a pop sound

C.

Evolves a lot of heat when burnt

D.

Dissociates to produce carbon (IV) oxide and oxygen

Correct answer is C

No explanation has been provided for this answer.

3,498.

Sodium metal is always kept under oil because it

A.

Readily reacts with water

B.

Is reduced by atmospheric nitrogen

C.

Reacts vigorously on exposure to air

D.

Reacts with oxygen and carbon (IV) oxide

Correct answer is C

No explanation has been provided for this answer.

3,499.

Transition metals possess variable oxidation states because they have

A.

Electrons in the d orbitals

B.

Electron in the s orbitals

C.

A variable number of electrons in the p orbitals

D.

Partially filled p orbitals

Correct answer is A

No explanation has been provided for this answer.

3,500.

Alloys are best prepared by

A.

Electroplating

B.

Arc-welding

C.

Reducing and mixture of their metallic oxide

D.

Cooling a molten mixture of the metals

Correct answer is D

No explanation has been provided for this answer.