Get started

Chemistry290Updated 11 Oct 202617 pages

Understanding Atom Economy: Definition and Calculation

Report
A
Ali @ali_wnmq
Add to Google sources
Ever wondered how chemists measure how wasteful a reaction is? Atom economy is chemistry's way of working out whether a reaction is environmentally friendly and cost-effective - basically, how much of your starting materials actually end up in the product you want rather than being wasted.
Atom Economy – page 1

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

What Is Atom Economy?

Think of atom economy like a recycling rate for chemical reactions. It measures how much of your starting materials (reactants) actually becomes the desired product you're trying to make.

When hydrogen and oxygen react to make water 2H2+O2→2H2O2H₂ + O₂ → 2H₂O, every single atom from the reactants ends up in the water molecules. This gives you a perfect 100% atom economy because nothing gets wasted.

Most reactions aren't this efficient though. You'll often get unwanted by-products that reduce the atom economy and make the process less sustainable.

Remember: Higher atom economy = less waste = better for both your wallet and the environment!

Atom Economy – page 2

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

Why Atom Economy Matters

Companies absolutely love reactions with high atom economy, and here's why. Cost-effectiveness is huge - if more of your expensive starting materials end up in your final product, you're not throwing money away on waste.

From an environmental perspective, high atom economy means sustainable development. You're using fewer raw materials and creating less chemical waste that needs disposing of.

Industries also prefer avoiding the headache of dealing with waste products. These often need special (and expensive) disposal methods, plus they take up storage space and can be hazardous.

Key point: In industrial chemistry, atom economy directly affects profit margins and environmental impact.

Atom Economy – page 3

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

The Atom Economy Formula

Here's the formula you need to memorise: Atom economy = (Mr of desired product / Mr of all reactants) × 100%

The relative formula mass (Mr) is just the total mass of all atoms in a compound. You calculate this using the periodic table - add up all the atomic masses for every atom in the formula.

While 100% atom economy would be ideal, it's rarely achievable in real reactions. Don't worry though - even 70-80% is considered pretty good in most industrial processes.

Pro tip: Always show your working clearly in calculations - examiners love to see each step laid out properly.

Atom Economy – page 4

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

Step-by-Step Calculations

Let's break down the calculation process into manageable chunks. Step 1: Work out the Mr for every single compound in the reaction - both reactants and products.

Step 2: Double-check your work by making sure the total mass of reactants equals the total mass of products. If they don't match, you've made an error somewhere.

Step 3: Apply the formula using only the Mr of your desired product (not all products) divided by the total Mr of all reactants, then multiply by 100 for the percentage.

Common mistake: Students often include unwanted by-products in the numerator - only use the desired product's mass!

Atom Economy – page 5

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

Worked Example: Calcium Carbonate

When calcium carbonate breaks down (CaCO₃ → CaO + CO₂), let's calculate the atom economy for producing calcium oxide. First, work out the Mr values: CaCO₃ = 100, CaO = 56, CO₂ = 44.

Check your masses: reactants = 100, products = 56 + 44 = 100 ✓. Now apply the formula: (56 ÷ 100) × 100 = 56% atom economy.

This means 44% of your starting material ends up as unwanted carbon dioxide gas. Not brilliant, but this reaction is still used industrially because calcium oxide is so valuable.

Real-world connection: This reaction happens in cement production - one of the world's biggest industries despite the relatively low atom economy.

Atom Economy – page 6

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

Practice Makes Perfect

The best way to master atom economy calculations is through loads of practice problems. Start with simpler reactions involving fewer compounds, then work up to more complex multi-step processes.

Remember that different products from the same reaction will have different atom economies. In glucose fermentation (C₆H₁₂O₆ → 2C₂H₅OH + 2CO₂), the atom economy for ethanol is about 51%.

Always double-check your arithmetic - it's easy to make silly mistakes with Mr calculations. Use the periodic table carefully and don't rush through the number crunching.

Exam tip: In longer questions, atom economy calculations often link to questions about industrial processes and environmental impact.

Atom Economy – page 7

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

Atom Economy – page 8

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

Atom Economy – page 9

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

Atom Economy – page 10

Sign up to see the content.
It's free!

By signing up you accept Terms of Service and Privacy Policy

We thought you’d never ask...

Our AI Companion is a student-focused AI tool that offers more than just answers. Built on millions of Knowunity resources, it provides relevant information, personalised study plans, quizzes, and content directly in the chat, adapting to your individual learning journey.

You can download the app from Google Play Store and Apple App Store.

That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.

Similar content

Chemistry

Quantitative Chemistry Essentials

Explore the fundamentals of Quantitative Chemistry, including balancing equations, mole calculations, and stoichiometry. This summary covers key concepts such as the conservation of mass, atom economy, and limiting reactants, providing a clear understanding of how to calculate moles and analyze chemical reactions effectively.

1167212
Chemistry

GCSE Chemistry Formulas

Essential formulas for GCSE Chemistry covering atom economy, gas volume calculations, concentration, yield, and reaction rates. Perfect for AQA, Edexcel, OCR, Eduqas, and Cambridge exam boards. Includes key tips for mastering calculations without a formula sheet.

111,0747
Chemistry

Chemistry: Key Concepts

Explore essential concepts in Higher Chemistry, including atom economy, dynamic equilibrium, titration techniques, and enthalpy changes. This summary covers calculations for theoretical and actual yields, bond enthalpy, and the impact of reactants in chemical reactions. Ideal for exam preparation and understanding core principles in chemistry.

S544911
Chemistry

Substance Measurement Essentials

Explore key concepts in physical chemistry, including relative atomic and molecular mass, Avogadro's constant, the ideal gas equation, empirical and molecular formulas, percentage yield, and atom economy. This summary provides essential calculations and principles for mastering mole concepts and stoichiometry.

126077
Chemistry

Concentration & Atom Economy

Explore the key concepts of concentration solutions and atom economy in chemical reactions. This summary covers how to calculate concentration in g/dm³, the significance of atom economy in evaluating reaction efficiency, and includes worked examples for practical understanding. Ideal for chemistry students preparing for exams.

10284
Chemistry

Maximizing Reactant Efficiency

Explore key concepts in maximizing reactant efficiency, including atom economy, limiting and excess reactants, percentage yield, and environmental considerations in industrial processes. This summary provides essential insights for Higher Chemistry students aiming to understand resource utilization and process design.

S51798
See more

Most popular content: Atom Economy

Chemistry

Hess's Law & Reaction Dynamics

Explore Hess's Law, enthalpy changes, and key concepts in reaction dynamics including atom economy, percent yield, and chemical equilibrium. This comprehensive summary covers essential calculations, energy diagrams, and chromatography techniques relevant to Higher Chemistry Unit 3. Ideal for students preparing for exams or seeking to deepen their understanding of chemical processes.

S52,51063
Chemistry

Maximizing Reactant Efficiency

Explore key concepts in maximizing reactant efficiency, including atom economy, limiting and excess reactants, percentage yield, and environmental considerations in industrial processes. This summary provides essential insights for Higher Chemistry students aiming to understand resource utilization and process design.

S51798
Chemistry

AMOUNT OF SUBSTANCE A-LEVEL CHEM NOTES

All notes of amount of substance for year 12 A level chemistry

1262
Chemistry

GCSE Chemistry Formulas

Essential formulas for GCSE Chemistry covering atom economy, gas volume calculations, concentration, yield, and reaction rates. Perfect for AQA, Edexcel, OCR, Eduqas, and Cambridge exam boards. Includes key tips for mastering calculations without a formula sheet.

111,0747
Chemistry

Concentration & Atom Economy

Explore the key concepts of concentration solutions and atom economy in chemical reactions. This summary covers how to calculate concentration in g/dm³, the significance of atom economy in evaluating reaction efficiency, and includes worked examples for practical understanding. Ideal for chemistry students preparing for exams.

10284
Chemistry

Mole Calculations & Equations

Explore essential mole calculations and chemical equations for OCR A Chemistry Topic 2. This resource covers stoichiometry, mole conversions, balancing equations, and the ideal gas equation, providing clear formulas and examples to enhance your understanding. Ideal for exam preparation and mastering key concepts in chemistry.

1234912

Most popular content: Chemistry

Chemistry

Chemisty Paper 1 Summary

Everything you need to know condensed into three pages

112,63362
Chemistry

A-level OCR A Chemistry summary sheets

Everything from snaprevise for OCR chemistry a-level

122,57690
Chemistry

BTEC Applied Science Unit 1 Overview

Comprehensive resource for Year 12 students pursuing a Level 3 Diploma in Applied Science. This booklet covers essential topics including cell structure, chemical properties, and wave theory, providing clear explanations and key concepts to aid in your studies and exam preparation.

125,663130
Chemistry

Redox Reactions Overview

Explore the fundamentals of redox reactions, including oxidation states, definitions of oxidation and reduction, and the roles of oxidizing and reducing agents. This summary covers key rules for determining oxidation states, the concept of disproportionation, and practical applications in chemical equations. Ideal for A-Level Chemistry students preparing for exams.

126,527324
Chemistry

Alevel Chemistry

Alevel Chemistry AQA

1231710
Chemistry

Redox Reactions & Periodicity

Explore key concepts in redox reactions, including oxidation and reduction processes, half-equations, and the role of oxidizing and reducing agents. Understand periodic trends such as electronegativity, ionization energy, and molecular structure. This summary covers essential topics for higher chemistry, focusing on the periodic table and intermolecular forces.

S53,326121
Biology

Comprehensive GCSE Science Overview

Explore a detailed compilation of key concepts across Biology, Chemistry, and Physics for the GCSE curriculum. This resource covers essential topics, including atomic structure, ecosystems, chemical reactions, and more, providing students with a thorough understanding to excel in their studies. Ideal for revision and exam preparation.

115,286644
Chemistry

GCSE Chemistry Revision Essentials

Comprehensive overview of key GCSE Chemistry topics including atomic structure, chemical bonding, reaction kinetics, and the periodic table. Ideal for Higher Tier students preparing for exams. Key concepts include mole calculations, electrolysis, and the Haber process.

93,09990
Chemistry

IGCSE Chemistry Concepts

Explore essential IGCSE Chemistry concepts including states of matter, chemical bonding, acid-base reactions, and separation methods. This comprehensive summary covers key topics such as ionic and covalent bonds, solubility rules, and the periodic table, tailored for Edexcel IGCSE Double Award students. Perfect for exam preparation and understanding fundamental chemistry principles.

111,46945

Most popular content

Sociology

Sociology of Families: Comprehensive Revision

Dive into an extensive overview of family dynamics, perspectives, and patterns in sociology. This resource covers key concepts such as family diversity, gender roles, marriage, and the impact of social policies on family structures. Perfect for A-Level Sociology students preparing for Paper 2.

1274,4062,310
Sociology

Sociology of Education Overview

Explore comprehensive A-Level Sociology notes on the education system, covering key theories, policies, and sociological perspectives. This resource includes insights on marketisation, gender roles, cultural deprivation, and educational inequalities, providing a thorough understanding of how education shapes social stratification and individual achievement. Ideal for exam preparation and in-depth study.

12103,7183,052
Sociology

Comprehensive Crime & Deviance Overview

Explore an extensive revision of crime and deviance topics, including theories, types of crime, and the impact of media. This resource covers key concepts such as Marxism, functionalism, gender and crime, and the influence of globalization on criminal behavior. Ideal for students seeking a thorough understanding of criminology and its various theories. Type: Full Topic Revision.

1252,2311,413
Biology

AQA Biology: Key Concepts

Explore essential AQA Biology topics including Photosynthesis, Respiration, Homeostasis, Genetics, and Ecology. This comprehensive knowledge organizer covers key concepts such as energy transfer, hormonal control, and genetic variation, providing a solid foundation for your studies. Ideal for exam preparation and understanding biological processes.

109,494321
English Literature

An Inspector Calls: Character Insights

Explore in-depth analysis and key quotes for characters in J.B. Priestley's 'An Inspector Calls'. This resource covers Gerald Croft, Inspector Goole, Sheila Birling, Mrs. Birling, Eric Birling, and Eva Smith, focusing on themes of class, gender roles, and social responsibility. Ideal for students aiming for Grade 8 and above.

1126,167924
Criminology

Criminal Justice Overview

Explore key concepts in criminal justice, including the trial process, roles of court personnel, types of offenses, and evidence handling. This comprehensive summary covers essential topics such as jury strengths and weaknesses, the role of the CPS, and the impact of media on trials. Ideal for students preparing for assessments in criminology. Achieved a B grade.

133,78678
Criminology

Criminal Justice Evidence Rules

Explore the essential rules governing the use of evidence in criminal cases, including reliability, admissibility, and relevance. This summary covers key concepts such as the roles of personnel in investigations, the impact of witness testimonies, and the implications of plea bargaining. Ideal for Year 13 criminology students preparing for assessments.

1211,505186
Sociology

Sociological Theories Overview

Comprehensive revision of key sociological theories including Functionalism, Marxism, Feminism, and Interpretivism. Explore concepts like value freedom, identity formation, and the critique of social control. Ideal for AQA A-Level Sociology students preparing for exams. This summary covers essential theories and their implications in sociology, providing a clear understanding of each perspective.

1232,016853
English Literature

An Inspector Calls: Character Insights

Explore the intricate character dynamics and themes in J.B. Priestley's 'An Inspector Calls'. This analysis covers key characters like Mrs. Birling, Sheila, Eric, and the Inspector, alongside themes of social responsibility, class, and gender inequality. Understand the historical context and Priestley's critique of capitalism. Ideal for students seeking a comprehensive understanding of the play's moral messages.

1113,849699

Students love us, and so will you.

4.6/5App Store
4.7/5Google Play
Stefan SiOS user

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Samantha KlichAndroid user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

AnnaiOS user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.