A student investigated the effects of different concentrations of copper(II) sulfate on the rate of a displacement reaction with zinc.
The student was given a stock solution of 0.80 mol dm-3 copper(II) sulfate and asked to prepare 40.0 cm3 of each of several dilutions.
Complete the table below to show how the student should prepare the solutions. All values must be written to one decimal place.
| Final concentration of solution (mol dm−3\text{mol dm}^{-3}mol dm−3) | Volume of 0.80 mol dm-3 copper(II) sulfate stock solution (cm3\text{cm}^3cm3) | Volume of distilled water (cm3\text{cm}^3cm3) | Final volume (cm3\text{cm}^3cm3) |
|---|---|---|---|
| 0.80 | 40.0 | ||
| 0.60 | 40.0 | ||
| 0.40 | 40.0 | ||
| 0.20 | 40.0 | ||
| 0.10 | 40.0 | ||
| 0.00 | 40.0 |
The copper(II) sulfate stock solution was prepared by measuring the mass of solid copper(II) sulfate on an electronic balance using a weighing bottle:
The balance recorded masses to two decimal places with an uncertainty of ±0.01 g\pm 0.01\text{ g}±0.01 g for each reading.
Calculate the percentage uncertainty in the mass of copper(II) sulfate. Show your working and round your final answer to two decimal places.
