NECO Past Questions and Answers - Page 108

536.

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.

537.

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.

538.

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.

539.

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.

540.

The position of an element in the Periodic Table is determined by?

A.

its atomic radius.

B.

its density.

C.

its relative atomic mass.

D.

the number of protons in its atom.

E.

the number of neutrons in its atoms

Correct answer is D

In the modern periodic table, the elements are listed in order of increasing atomic number. 

The atomic number is the number of protons in the nucleus of an atom.