MCQ Tip Talk 2: Spot the “controversial” MCQ statement

[17 Feb 2023]

In today’s ✨MCQ Tip Talk #2, let’s look at this question to identify more common tricks used by examination setters.

Q: Sarah left a glass of water with ice on the dining table. After 5 minutes, she observed that droplets of water had appeared on the outer surface of the glass of water as shown below.

Which one of the following statements best explains her observation?

1) The water in the glass had lost heat to the surrounding air and condensed on the outer surface of the glass.

2) The water vapour in the surrounding air had gained coldness from the outer surface of the glass and condensed on it.

3) The water vapour in the surrounding air had lost heat to the outer surface of the glass and condensed on it.

4) Some of the water had leaked from the inside of the glass. 

Let’s Break it Down: 

Statement 1: 
The water in the glass had lost heat to the surrounding air and condensed on the outer surface of the glass. 
❌This is the obvious erroneous statement with the wrong concept used.

Statement 2:
The water vapour in the surrounding air had gained coldness from the outer surface of the glass and condensed on it.
❌This is the erroneous statement with the wrong words/concept used.

Statement 3:
The water vapour in the surrounding air had lost heat to the outer surface of the glass and condensed on it.
✔️This is the correct statement.

How about Statement 4?

Let me will Introduce to you what I term the “controversial” statement.

Statement 4:
Some of the water had leaked from the inside of the glass.
❌Not possible to tell! It is simply not possible to conclude from the information given in the question to prove this statement is definitely true. Yet the notion that some water may have leaked is not entirely impossible, causing some students to entertain it as plausible answer.

Share this with your child today!