Sodium hydrogencarbonate decomposes when heated.
2NaHCO3→Na2CO3+CO2+H2O\mathrm{2NaHCO_3 \rightarrow Na_2CO_3 + CO_2 + H_2O}2NaHCO3→Na2CO3+CO2+H2O
A student heated sodium hydrogencarbonate in an evaporating basin. The solid product was sodium carbonate.
| Measurement | Mass in g |
|---|---|
| Sodium hydrogencarbonate heated | 21.0 |
| Empty evaporating basin | 35.60 |
| Evaporating basin and dry sodium carbonate | 46.20 |
| Substance | Relative formula mass (MrM_rMr) |
|---|---|
| NaHCO3\mathrm{NaHCO_3}NaHCO3 | 84.0 |
| Na2CO3\mathrm{Na_2CO_3}Na2CO3 | 106.0 |
Calculate the percentage yield of sodium carbonate.
Give your answer to 3 significant figures.
104 exam-style questions on AQA GCSE Chemistry 3.3 Yield and atom economy of chemical reactions, covering 3.3.1a Percentage yield, 3.3.1b Theoretical mass of a product, 3.3.2a Atom economy, and 3.3.2b Choosing a reaction pathway. Each one has a worked solution and a mark scheme showing where the marks go.