Urea, CO(NH2)2\text{CO(NH}_2)_2CO(NH2)2, is an important industrial compound widely used as a nitrogen-rich fertilizer.
It is manufactured on an industrial scale by reacting ammonia with carbon dioxide:
2NH3(g)+CO2(g)→CO(NH2)2(s)+H2O(l) 2\text{NH}_3\text{(g)} + \text{CO}_2\text{(g)} \rightarrow \text{CO(NH}_2)_2\text{(s)} + \text{H}_2\text{O(l)} 2NH3(g)+CO2(g)→CO(NH2)2(s)+H2O(l)Calculate the atom economy for the production of urea, CO(NH2)2\text{CO(NH}_2)_2CO(NH2)2, in this reaction.
(relative atomic masses: H=1.0\text{H} = 1.0H=1.0, C=12.0\text{C} = 12.0C=12.0, N=14.0\text{N} = 14.0N=14.0, O=16.0\text{O} = 16.0O=16.0
relative formula masses: NH3=17.0\text{NH}_3 = 17.0NH3=17.0, CO2=44.0\text{CO}_2 = 44.0CO2=44.0, CO(NH2)2=60.0\text{CO(NH}_2)_2 = 60.0CO(NH2)2=60.0, H2O=18.0\text{H}_2\text{O} = 18.0H2O=18.0)
Give your answer to three significant figures.
119 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.