Tungsten is a high-strength transition metal widely used in rocket engine nozzles and incandescent filaments due to its extremely high melting point.
Tungsten can be industrially obtained by reducing tungsten(VI) oxide with hydrogen gas at high temperatures:
WO3+3H2→W+3H2O \text{WO}_3 + 3\text{H}_2 \rightarrow \text{W} + 3\text{H}_2\text{O} WO3+3H2→W+3H2OCalculate the percentage atom economy for the production of tungsten, W\text{W}W, in this reaction.
(relative atomic masses: H=1.0\text{H} = 1.0H=1.0, O=16.0\text{O} = 16.0O=16.0, W=183.8\text{W} = 183.8W=183.8
relative formula masses: H2=2.0\text{H}_2 = 2.0H2=2.0, WO3=231.8\text{WO}_3 = 231.8WO3=231.8)
Give your answer to two significant figures.
Practise Edexcel GCSE Chemistry Quantitative analysis with exam-style questions for Foundation and Higher tier. 100 questions, matched to the Edexcel GCSE Chemistry (1CH0) specification and written in Paper 1 and Paper 2 style. Every question includes a full worked solution and mark scheme, so you can see where marks are awarded rather than just whether you got the answer right.