The percentage yield of a chemical reaction can be calculated using the formula:
percentage yield=actual yieldtheoretical yield×100 \text{percentage yield} = \frac{\text{actual yield}}{\text{theoretical yield}} \times 100 percentage yield=theoretical yieldactual yield×100During a laboratory preparation of biodiesel (methyl esters) from a vegetable oil feedstock, a student recorded the data shown in Table 1.
Calculate the percentage yield of biodiesel obtained in this preparation.
Table 1
| Mass in g | |
|---|---|
| Mass of vegetable oil feedstock used | 28.40 |
| Mass of biodiesel obtained from the reaction | 21.06 |
| Theoretical mass of biodiesel formed | 27.00 |
157 exam-style questions on Edexcel GCSE Chemistry 6.2 Quantitative analysis, covering 6.2.1 Concentration in mol dm⁻³ and titration calculations, 6.2.2 Percentage yield and why actual yield falls short, 6.2.3 Atom economy of a reaction, 6.2.4 Choosing a reaction pathway, and 6.2.5 Molar volume of gases and Avogadro's law. Each one has a worked solution and a mark scheme showing where the marks go.