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.

2,636.

Which of the following physical properties decreases across the Periodic Table?

A.

Ionization potenial

B.

Electron affinity

C.

Electronegativity

D.

Atomic radius

Correct answer is D

No explanation has been provided for this answer.

2,637.

A metallic ion X2+ with an inert gas structure contains 18 electrons. How many protons are there in this ion?

A.

20

B.

18

C.

16

D.

2

Correct answer is A

No explanation has been provided for this answer.

2,639.

An increase in temperature causes an increase in the pressure of a gas because there is an increase in the?

A.

average velocity of the molecules

B.

number of collisions between the molecules

C.

density of the molecules

D.

free mean path between each molecules and other

Correct answer is B

No explanation has been provided for this answer.

2,640.

One mole of propane is mixed with five moles of oxygen. The mixture is ignited and the propane burns completely. What is the volume of the products at s.t.p?

(G.M.V = 22.4 dm3 mol-1)

A.

112.0 dm3

B.

67.2 dm3

C.

56.0 dm3

D.

44.8 dm3

Correct answer is B

C3H8 + 5O2 → 3CO2 + 4H2O
When the mixture is ignited CO2 is collected as product. From the equation 33 moles of CO2 is produced which equals 3 x 2.4 dm3 = 67.2 dm3 at S.T.P