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.

1,631.

Which of the following quantities is the same for one mole of Br2(l) and one mole of He(g)?

A.

Number of molecules

B.

Number of atoms

C.

Total mass of the particles

D.

Volume occupied at s.t.p

Correct answer is A

No explanation has been provided for this answer.

1,632.

Which of the following statements about dative bonding is not correct?

A.

there is sharing of electrons

B.

one atom must possess a lone pair electrons

C.

each participating atom contributes one electron

D.

it can be formed between molecules

Correct answer is C

No explanation has been provided for this answer.

1,633.

An element X with electronic configuration \(1S^22S^22P^63S^2\) combines with another element Y with the configuration \(1S^2S^22P^23S^23P^5\). What is the formula of the compound formed?

A.

X2Y5

B.

X2Y3

C.

XY3

D.

XY2

Correct answer is D

Element X has a valency of 2 while Y has a valency of 1,

so they exchange valency to form \( XY_2\)

1,634.

Group O of elements are unreactive because

A.

their outmost shells contain equal number of electrons

B.

their highest occupied enegy level is full

C.

they are monatomic gases

D.

they are non-metals

Correct answer is B

No explanation has been provided for this answer.

1,635.

The electronic configuration of an element is 1\(s^2\) 2\(s^2\) 2\(p^6\) 3\(s^2\) 3\(p^3\). Where is the element located in the periodic table?

A.

Group lll, period 3

B.

Group lll, period 5

C.

Group V, period 3

D.

Group V, period 5

Correct answer is C

the element belongs to group 5, since we have two coefficients that are the same we simply add the powers that give 5. while the highest coefficient gives the period that is 3.

therefore, the element is found in group 5 period 3.