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===About Atom Economy===
: During a [[Chemical Reaction|chemical reaction]] there is often more than one [[product]]. When there is more than one [[product]] often one is desired and one is a [[Waste Product|waste product]] that must be [[disposal|disposed]] of.: To reduce costs and increase the [[efficiency]] of a process [[Chemical Engineer|chemical engineers]] design systems that [[product|produce]] the maximum amount of a desired [[product]] and a minimum amount of [[Waste Products|waste products]].
===Atom Economy Equation===
Percentage Atom Economy = [(Relative Formula Mass of Desired Product)/(Sum of Relative Formula Masses of Reactants)] x 100%
'' '''% Atom Economy ''' '' = <math>\frac{M_desiredproductM_p}{M_allreactantsM_r}\times 100%</math>
Where:
M<sub>desiredproductp</sub> = Relative Formula Mass of Desired Product
M<sub>allreactantsr</sub> = Sum of Relative Formula Masses of Reactants
===Example Calculations===
{| class="wikitable"
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Calculate the '''atom economy''' for [[product|producing]] [[Ammonia]] in the following [[Chemical Reaction|reaction]]:
N<sub>2</sub>(g) + 3H<sub>2</sub>(g) ⇌ 2NH<sub>3</sub>(g)
| style="height:20px; width:300px; text-align:center;" |
Calculate the '''atom economy''' for [[product|producing]] [[Calcium Oxide]] in the following [[Chemical Reaction|reaction]]:
CaCO<sub>3</sub>(s) → CaO(s) + CO<sub>2</sub>(g)
| style="height:20px; width:300px; text-align:center;" |
Calculate the '''atom economy''' for [[product|producing]] [[Sodium Chloride]] in the following [[Chemical Reaction|reaction]]:
HCl(aq) + NaOH(aq) → NaCl(aq) + H<sub>2</sub>O(l)
|-
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'''Find the [[Relative Formula Mass]] of the relevant [[reactant]]s and [[product]].'''
M<sub>r</sub> of N<sub>2</sub> = 28g
M<sub>r</sub> of H<sub>2</sub> = 2g
M<sub>r</sub> of NH<sub>3</sub> = 17g
| style="height:20px; width:300px; text-align:left;" |
'''Find the [[Relative Formula Mass]] of the relevant [[reactant]]s and [[product]].'''
M<sub>r</sub> of CaCO<sub>3</sub> = 100g
M<sub>r</sub> of CaO = 56g
| style="height:20px; width:300px; text-align:left;" |
'''Find the [[Relative Formula Mass]] of the relevant [[reactant]]s and [[product]].'''
M<sub>r</sub> of HCl = 36.5g
M<sub>r</sub> of NaOH = 40g
M<sub>r</sub> of NaCl = 58.5g
|-
| style="height:20px; width:300px; text-align:left;" |
'''Find the total [[mass]] of [[reactant]]s needed and the total [[mass]] of the desired [[product]].'''
Mass of Reactants = 28 + 3 x 2
Mass of Reactants = 34g
Mass of desired Product = 2 x 17
Mass of desired Product = 34g
| style="height:20px; width:300px; text-align:left;" |
'''Find the total [[mass]] of [[reactant]]s needed and the total [[mass]] of the desired [[product]].'''
Mass of Reactants = 100g
Mass of desired Product = 56g
| style="height:20px; width:300px; text-align:left;" |
'''Find the total [[mass]] of [[reactant]]s needed and the total [[mass]] of the desired [[product]].'''
Mass of Reactants = 36.5 + 40
Mass of Reactants = 76.5g
Mass of desired Product = 58.5g
|-
| style="height:20px; width:300px; text-align:left;" |
'''Substitute the values into the equation.'''
'' '''% Atom Economy''' '' = <math>\frac{M_p}{M_r} \times 100%</math>
'' '''% Atom Economy''' '' = <math>\frac{34}{34} \times 100%</math>
'' '''% Atom Economy''' '' = 100%
| style="height:20px; width:300px; text-align:left;" |
'''Substitute the values into the equation.'''
'' '''% Atom Economy''' '' = <math>\frac{M_p}{M_r} \times 100%</math>
'' '''% Atom Economy''' '' = <math>\frac{56}{100} \times 100%</math>
'' '''% Atom Economy''' '' = 56%
| style="height:20px; width:300px; text-align:left;" |
'''Substitute the values into the equation.'''
'' '''% Atom Economy''' '' = <math>\frac{M_p}{M_r} \times 100%</math>
'' '''% Atom Economy''' '' = <math>\frac{58.5}{76.5} \times 100%</math>
'' '''% Atom Economy''' '' = 76.5%
|}
===References===
====AQA====
:[https://www.amazon.co.uk/gp/product/1471851346/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1471851346&linkCode=as2&tag=nrjc-21&linkId=3ac654f4b0da781c49c855a1af4c92ea ''Atom economy (atom utilisation), pages 79-80, GCSE Chemistry, Hodder, AQA '']
:[https://www.amazon.co.uk/gp/product/1782945571/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945571&linkCode=as2&tag=nrjc-21&linkId=9e29fad914244909903e5e93f8a01d47 ''Atom economy, page 48, GCSE Chemistry; The Revision Guide, CGP, AQA '']
:[https://www.amazon.co.uk/gp/product/1782945962/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945962&linkCode=as2&tag=nrjc-21&linkId=476bb5c8d1dfb5c08ac81b6d4d1c98d8 ''Atom economy, pages 138-140, GCSE Chemistry, CGP, AQA '']
:[https://www.amazon.co.uk/gp/product/0198359381/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359381&linkCode=as2&tag=nrjc-21&linkId=47c8d1ae58d8b3a5e2094cd447154558 ''Atom economy, pages 70-71, GCSE Chemistry; Third Edition, Oxford University Press, AQA '']
:[https://www.amazon.co.uk/gp/product/0008158762/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0008158762&linkCode=as2&tag=nrjc-21&linkId=a0fffa35b3ea49a63404f6704e0df7cc ''Atom; atom economy (atom utilisation), pages 97, 116-7, 323, 325, GCSE Chemistry; Student Book, Collins, AQA '']
====Edexcel====
:[https://www.amazon.co.uk/gp/product/1782945725/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945725&linkCode=as2&tag=nrjc-21&linkId=694be7494de75af3349537d34e13f7f0 ''Atom economies, page 67, GCSE Chemistry; The Revision Guide, CGP, Edexcel '']
:[https://www.amazon.co.uk/gp/product/1782948147/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782948147&linkCode=as2&tag=nrjc-21&linkId=f63dcd8345f4e49c717b39a228a36c7c ''Atom economies, pages 192-194, GCSE Chemistry, CGP, Edexcel '']
:[https://www.amazon.co.uk/gp/product/1292120215/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1292120215&linkCode=as2&tag=nrjc-21&linkId=8f96ddb76196848bafdb124354e4cf77 ''Atom economy, pages 110-111, GCSE Chemistry, Pearson, Edexcel '']
====OCR====
:[https://www.amazon.co.uk/gp/product/0198359829/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=0198359829&linkCode=as2&tag=nrjc-21&linkId=90e8d7b4f039d53035238fa0320fe00b ''Atom economies, page 161, Gateway GCSE Chemistry, Oxford, OCR '']
:[https://www.amazon.co.uk/gp/product/1782945679/ref=as_li_tl?ie=UTF8&camp=1634&creative=6738&creativeASIN=1782945679&linkCode=as2&tag=nrjc-21&linkId=a2db42f7b4bdf10cafaafa3bb9120940 ''Atom economy, page 67, GCSE Chemistry; The Revision Guide, CGP, OCR Gateway '']