WAEC Past Questions and Answers - Page 1473

7,361.

Which of the following compounds would dissolved in water to give a solution whose pH is less than 7?

A.

AI(NO3)3

B.

KNO3

C.

N2O

D.

NH3

Correct answer is A

No explanation has been provided for this answer.

7,362.

An aqueous solution of CaCI2 is

A.

acidic solution

B.

alkaline solution

C.

a buffer solution

D.

a neutral solution

Correct answer is D

No explanation has been provided for this answer.

7,363.

The colour of phenolphthalein indicator in dilute HNO is

A.

colourless

B.

orange

C.

pink

D.

purple

Correct answer is A

No explanation has been provided for this answer.

7,364.

Which of the following set of equations could be used to represent the standard enthalpy of formation of glucose?

A.

6C (s) + 6H 2(g) + 3O2(g) → C 6H12O6(s)

B.

6CO2(g) + 6H2O (l) → C6H12O6(s) + 6O 2(g)

C.

6C(g) + 6H 2(g) + 3O2(g) → C6H12O 6(s)

D.

6C(g) + 6H 2(g) + 3O2(g) → C 6H 12O 6(aq)

Correct answer is B

No explanation has been provided for this answer.

7,365.

Diamond does not conduct electricity because it?

A.

has no free valence electrons

B.

is a giant molecule

C.

contains no bonded electrons

D.

is a solid at room temperature

Correct answer is A

It does not conduct electricity. Every atom in a diamond is bonded to its neighbours by four strong covalent bonds, leaving no free electrons and no ions .