STAT Scientific and Mathematical Reasoning 5

Question 1

A solution turns red litmus paper blue. Which of the following is most consistent with this observation?

Accepted Answer

The solution contains excess OH⁻ ions

Answer

Red litmus turns blue in basic (alkaline) solutions, which have a pH above 7 and excess hydroxide ions.

Question 2

Three friends run a race. Their finishing times in seconds are 52, 58, 48, 61, and 46. What is the median finishing time?

Accepted Answer

52

Answer

Ordered: 46, 48, 52, 58, 61; the middle value (3rd of 5) is 52 seconds.

Question 3

A chemical reaction produces a gas that extinguishes a burning splint. Which gas was most likely produced?

Accepted Answer

Carbon dioxide

Answer

Carbon dioxide does not support combustion and will extinguish a burning splint (oxygen relights a glowing splint; hydrogen burns with a squeaky pop).

Question 4

If the probability of event X occurring is 0.3 and the probability of event Y occurring is 0.5, and the two events are independent, what is the probability that neither X nor Y occurs?

Accepted Answer

0.35

Answer

P(not X) = 0.7, P(not Y) = 0.5; P(neither) = 0.7 × 0.5 = 0.35.

Question 5

A student notices that ice melts faster in a black container than in a white container when both are placed in sunlight. The best scientific explanation is:

Accepted Answer

Black surfaces absorb more radiant energy than white surfaces

Answer

Dark surfaces absorb more electromagnetic radiation and convert it to heat, accelerating the melting of the ice.

STAT - Special Tertiary Admissions Test Practice Test

STAT - Special Tertiary Admissions Test Practice Test

STAT Scientific and Mathematical Reasoning 5