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.

2,216.

In the diagram above, R is a mixture of?

A.

potassium tetraxochlorate (VII) and concentrated H2SO4

B.

potassium trioxochlorate (V) and concentrated H2SO4

C.

potassium tetratoxomanganate (VII) and concentrated HCI

D.

manganes (IV) oxide and concentrated HCI

Correct answer is D

No explanation has been provided for this answer.

2,217.

2HCL(ag) + CaCO3(ag) → CaCL2(ag) + H2O(1) + CO from the reaction above, which of the following curves represents the consumption of calcium trioxocarbonate (IV) as dilute HCL is added to it?

A.

L

B.

M

C.

N

D.

P

Correct answer is D

The concentration of the \(CaCO_3\) decreases as reaction time decreases. therefore option D is correct.

2,218.

In the diagram above the activation energy is represented by

A.

y - x

B.

x

C.

x - z

D.

y

Correct answer is A

No explanation has been provided for this answer.

2,219.

The ∆H for the reaction represented by the energy profile above is

A.

-100 kJ mol--1

B.

+ 100 kJ mol-1

C.

+50 kJ mol-1

D.

-50 kJ mol-1

Correct answer is D

No explanation has been provided for this answer.

2,220.

The set-up above would be useful for determining the amount of

A.

oxygen in air

B.

water vapour in air

C.

CO2 in air

D.

arygen in air

Correct answer is B

No explanation has been provided for this answer.