A laboratory stores nitric acid as a stock solution. An analyst removes some of the stock and prepares a test solution with distilled water.
| Measurement | Volume (cm3\mathrm{cm^{3}}cm3) |
|---|---|
| Stock solution used | 10.0 |
| Final volume of test solution | 200 |
A sample of the test solution is placed in a conical flask. Potassium hydroxide solution is delivered from a burette until the reaction is complete.
| Measurement | Value |
|---|---|
| Volume of test solution in the flask | 20.0 cm320.0\,\mathrm{cm^{3}}20.0cm3 |
| Concentration of potassium hydroxide | 0.150 mol/dm30.150\,\mathrm{mol/dm^{3}}0.150mol/dm3 |
| Volume delivered from the burette | 16.40 cm316.40\,\mathrm{cm^{3}}16.40cm3 |
The equation for the reaction is:
HNO3+KOH→KNO3+H2O \mathrm{HNO_{3}} + \mathrm{KOH} \rightarrow \mathrm{KNO_{3}} + \mathrm{H_{2}O} HNO3+KOH→KNO3+H2OUse the results to calculate the stock solution's concentration of HNO3\mathrm{HNO_{3}}HNO3.
Give your answer in mol/dm3\mathrm{mol/dm^{3}}mol/dm3.
Concentration = .................... mol/dm3\mathrm{mol/dm^{3}}mol/dm3
152 exam-style questions on OCR GCSE Chemistry 5.1 Monitoring chemical reactions, covering 5.1.1 The technique of titration, 5.1.2 Theoretical mass, percentage yield and atom economy, 5.1.3 Concentration of a solution in mol/dm3, 5.1.4 Concentration calculations and titration results, 5.1.5 Molar gas volume and volumes of gases in reactions, and 5.1.6 Choosing a reaction pathway. Each one has a worked solution and a mark scheme showing where the marks go.