CIE iGCSE Co-Ordinated Science B3.1 Diffusion Exam Style Questions Paper 2
Question
Which conditions will result in the fastest rate of diffusion?
▶️Answer/Explanation
Ans : A
Question
What is the effect of increasing the concentration gradient on the rate of diffusion?
▶️Answer/Explanation
Answer: C
Question
What is the net movement of molecules during diffusion?
A. from a higher concentration to a lower concentration down a concentration gradient
B. from a higher concentration to a lower concentration up a concentration gradient
C. from a lower concentration to a higher concentration down a concentration gradient
D. from a lower concentration to a higher concentration up a concentration gradient
▶️Answer/Explanation
Answer: A
Explanation: Diffusion is the net movement of particles from an area of higher concentration to an area of lower concentration, down the concentration gradient. This process occurs due to the random motion of particles and does not require energy input.
Question
Which row correctly describes the diffusion of molecules from P to Q?
| P | Q | movement | |
|---|---|---|---|
| A | higher concentration | lower concentration | down a concentration gradient |
| B | higher concentration | lower concentration | up a concentration gradient |
| C | lower concentration | higher concentration | down a concentration gradient |
| D | lower concentration | higher concentration | up a concentration gradient |
▶️Answer/Explanation
Answer: A
Explanation: Diffusion is the net movement of particles from a region of higher concentration to lower concentration (down the concentration gradient). Movement from lower to higher concentration would require energy (active transport).