Ammonia (NH3\text{NH}_3NH3) is industrially recovered from ammonium chloride (NH4Cl\text{NH}_4\text{Cl}NH4Cl) by reaction with calcium hydroxide (Ca(OH)2\text{Ca(OH)}_2Ca(OH)2) according to the following equation:
2NH4Cl+Ca(OH)2⟶CaCl2+2NH3+2H2O 2\text{NH}_4\text{Cl} + \text{Ca(OH)}_2 \longrightarrow \text{CaCl}_2 + 2\text{NH}_3 + 2\text{H}_2\text{O} 2NH4Cl+Ca(OH)2⟶CaCl2+2NH3+2H2OWhat is the percentage atom economy for the production of ammonia in this reaction?
(Mr M_r\,Mr values: NH4Cl=53.5\text{NH}_4\text{Cl} = 53.5NH4Cl=53.5, Ca(OH)2=74.1\text{Ca(OH)}_2 = 74.1Ca(OH)2=74.1, CaCl2=111.1\text{CaCl}_2 = 111.1CaCl2=111.1, NH3=17.0\text{NH}_3 = 17.0NH3=17.0, H2O=18.0\text{H}_2\text{O} = 18.0H2O=18.0)
9.4%9.4\%9.4%
13.3%13.3\%13.3%
18.8%18.8\%18.8%
26.6%26.6\%26.6%
91 exam-style questions on OCR GCSE Chemistry Monitoring chemical reactions. Each one has a worked solution and a mark scheme showing where the marks go.