NECO Chemistry Past Questions & Answers - Page 32

156.

The alloy used for welding and plumbing contains

A.

aluminum and copper.

B.

copper and tin

C.

iron and aluminum.

D.

lead and antimony.

E.

lead and tin.

Correct answer is E

No explanation has been provided for this answer.

157.

In any chemical reaction, the total mass of products is always equal to that of the reactants.

This Is statement of the law of:

A.

conservation of matter.

B.

Constant composition

C.

definite proportions.

D.

multiple proportions.

E.

reciprocal proportions.

Correct answer is A

No explanation has been provided for this answer.

158.

Which metal will dissolve in aqueous sodium hydroxide?

A.

aluminium

B.

copper

C.

iron

D.

sikeer

E.

tin

Correct answer is A

No explanation has been provided for this answer.

159.

Which compound can be used as a reducing agent in a reaction?

A.

Cl2

B.

KMnO4

C.

KCr2O7

D.

MnO2

E.

Na2SO3

Correct answer is E

No explanation has been provided for this answer.

160.

what dose the following equation illustrate? \( ^{238}U_{92} → ^{234}Th_{90} + ^4 He_2 \)

A.

Artificial radioactivity

B.

nuclear fission

C.

nuclear fusion

D.

radio-decomposition

E.

spontaneous disintegration

Correct answer is E

No explanation has been provided for this answer.