WAEC Chemistry Past Questions & Answers - Page 165

821.

A transition metal would be expected to

A.

from oxides with different formulae

B.

have strong oxidizing ability

C.

have low density

D.

have an atomic structure with an incomplete outermost shell

Correct answer is A

No explanation has been provided for this answer.

822.

In which of the following atoms is the ionic radius larger than the atomic radius? [11 Na, 12Mg,13AI,17CI]

A.

Aluminium

B.

Chlorine

C.

Magnesium

D.

Sodium

Correct answer is B

No explanation has been provided for this answer.

823.

Which of the following properties is characteristic of the halogens?

A.

Ability to accept electrons readily

B.

Ability to donate electrons readily

C.

Ability to from basic oxides

D.

Formation of coloured compounds

Correct answer is A

No explanation has been provided for this answer.

824.

Which of the following statements about rare gases are correct?

A.

Their outermost shells are fully filled

B.

They are generally unreactive

C.

Their outermost shells are partially filled

D.

They have lone pair of

Correct answer is A

No explanation has been provided for this answer.

825.

When sodium atom form the ion Na+,

A.

it gains one proton

B.

it achieves a noble gas configuration

C.

its atomic number increases

D.

it gains one electron

Correct answer is B

When the sodium atom forms an ion, Na+ it loses one electron, i.e. it achieves a noble gas electronic configuration. It will lose one of its 11 electrons to have 10 electrons like neon.
\(Na - e^- → Na^+\)
Na → \(Na^+ + e^-\)