Reversible reactions in a sealed container
3 marks · EasyA student records the number of red and green squares at different times in a sealed container during a reversible reaction.
| Time (s) | Red squares | Green squares |
|---|---|---|
| 0 | 40 | 0 |
| 1 | 30 | 10 |
| 2 | 23 | 17 |
| 3 | 19 | 21 |
How many total squares are there in the container at each recorded time?
What does this suggest about the system in the container?
State what feature of the container ensures this result in a reversible reaction.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
(a) 40 squares at each time. · must show sum to 40 at each interval
(b) No squares are lost or gained. · must show system is closed or sealed
(c) The container is sealed. · must show sealed container
Show mark scheme and worked solution
Marking points
B1 (a) · 1 mark · Recognises that the total number of squares is unchanged (40) at all times.
B1 (b) · 1 mark · States no squares are lost/gained, or that the system is closed/sealed.
B1 (c) · 1 mark · Identifies sealed container as the reason.
Worked solution
a) Total squares: 40 at each time (0 s: 40+0=40, 1 s: 30+10=40, 2 s: 23+17=40, 3 s: 19+21=40).
b) This suggests that there is no loss or gain of squares in the system.
c) This is because the container is sealed.