WAEC Past Questions and Answers - Page 4077

20,381.

Which of the following reagents is used to test for starch?

A.

Million’s reagent

B.

Fehling’s solution

C.

Sudan III

D.

Iodine solution

E.

Benedict’s solution

Correct answer is D

No explanation has been provided for this answer.

20,382.

The half-life of a radioactive element is 5 Calculate its decay constant

A.

0.113s-1

B.

0.436 s-1

C.

0.139 s-1

D.

0.193 s-1.

Correct answer is C

No explanation has been provided for this answer.

20,383.

Which of the following is a nitrifying bacterium

A.

Nitrobacter

B.

Rhizobium

C.

Azotobacter

D.

Clostridium

E.

Nitrosomonas

Correct answer is A

No explanation has been provided for this answer.

20,384.

Two chords PQ and RS of a circle when produced meet at K. If ∠KPS = 31o and ∠PKR = 42o, find ∠KQR

A.

11o

B.

73o

C.

107o

D.

138o

E.

149o

Correct answer is C

No explanation has been provided for this answer.

20,385.

Thunderstorm can be beneficial to plants because it

A.

kills the pests that attacks crops

B.

destroys some of the major crops

C.

adds nitrates to the soil

D.

adds lime to the soil

E.

makes rain water available to plants

Correct answer is C

No explanation has been provided for this answer.