A chemist makes sodium chloride in a laboratory using the reaction:
2Na+Cl2→2NaCl2\text{Na} + \text{Cl}_2 \rightarrow 2\text{NaCl}2Na+Cl2→2NaCl
The chemist reacts 4.60 g of sodium with 3.20 g of chlorine. The sodium chloride is separated from the reaction mixture, and 4.22 g is collected.
Relative atomic masses: Na = 23, Cl = 35.5.
Calculate the greatest mass of sodium chloride, in grams, that these amounts of sodium and chlorine could produce.
The chemist's target was a percentage yield of at least 85 %. Calculate how much more sodium chloride, in grams, would have needed to be collected to meet this target.
The chemist collected less sodium chloride than the calculated maximum. Give one possible cause of this shortfall.
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.