Question 7
SECTION 3, QUESTION 5
Student B used the same steps in the experiment and obtained readings for three salt solutions. They are tabulated below:
| Concentration of salt solution (g/l) | G reading: 1st (units) | 2nd | 3rd |
| --- | --- | --- | --- |
| 40 | 16 | 18 | 16 |
| 180 | 79 | 82 | 80 |
| 250 | 111 | 112 | 113 |
In the grid on the next page, plot a graph to show how the reading on instrument G changes with the concentration of the salt solution. Show on the graph, how you would estimate the concentration of salt solution, S1. [6 marks]
Estimated concentration of S1: __________ g/l
Student B used the same steps in the experiment and obtained readings for three salt solutions. They are tabulated below:
| Concentration of salt solution (g/l) | G reading: 1st (units) | 2nd | 3rd |
| --- | --- | --- | --- |
| 40 | 16 | 18 | 16 |
| 180 | 79 | 82 | 80 |
| 250 | 111 | 112 | 113 |
In the grid on the next page, plot a graph to show how the reading on instrument G changes with the concentration of the salt solution. Show on the graph, how you would estimate the concentration of salt solution, S1. [6 marks]
Estimated concentration of S1: __________ g/l