Atom Economy

This lesson covers:

  1. What 'atom economy' is, and how to calculate it
  2. Why it's important for chemists to consider atom economy 
  3. How to improve atom economy 

What is the atom economy of a reaction?

The actual yield compared to the maximum theoretical yield

A measure of the proportion of starting materials that end up as useful products

The number of atoms that do not end up as useful products

0

/

1

2H2O2 → 2H2O + O2


Calculate the atom economy when forming oxygen from hydrogen peroxide. Give your answer to 3.s.f.

(Ar of H is 1, Ar of O is 16)

47.1

%

%

0

/

1

2Na + Cl2 ➔ 2NaCl


Without doing any calculations, what is the atom economy of the above reaction? 

100

%

%

0

/

1

Fe2O3 + 3CO ➔ 2Fe + 3CO2


Calculate the atom economy when forming carbon dioxide from iron (III) oxide and carbon monoxide. Give your answer to 3 s.f.


(Ar of Fe is 56, Ar of C is 12, Ar of O is 16)

54.1

%

%

0

/

1

What are the problems with low atom economy? 

(Select all that apply)

It will be less sustainable as it will use more resources

It gives a low percentage yield

The reaction will be slow

There will be more waste products which will have to be disposed of

0

/

2

Ba(OH)2 + H2SO4 ➔ BaSO4 + 2H2O


Calculate the atom economy when making barium sulfate from barium hydroxide and sulfuric acid. Give your answer to 3.s.f.


(You may need a periodic table)

86.6

%

%

0

/

1

Identify 3 other factors, besides atom economy, that should be considered when choosing between two different methods of producing a useful product.

0

/

3