3.1 Getting The Most From Reactants

Question 1

What are the factors influencing industrial process?

Answer 1

-availability, sustainability and cost of feedstock(s)
-opportunities for recycling
-energy requirements
-marketability of by-products
-product yield

Question 2

What are the environmental considerations?

Answer 2

-minimising waste
-avoiding the use or production of toxic substances
-designing products which will biodegrade if appropriate

Question 3

What is molar volume?

Answer 3

The molar volume (litres mol⁻¹) is the volume occupied by one mole of any gas at a certain temperature and pressure. The molar volume is the same for all gases at the same temperature and pressure.

Question 4

What is theoretical yield?

Answer 4

The ‘theoretical yield’ is the quantity of desired product obtained, assuming full conversion of the limiting reagent, as calculated from the balanced equation.

Question 5

What is actual yield?

Answer 5

The ‘actual yield’ is the quantity of the desired product formed under the prevailing reaction conditions

Question 6

How do u calculate % yield?

Answer 6

Actual yield%
————————- x 100
Theoretical yield%

Question 7

What is atom economy?

Answer 7

The atom economy measures the proportion of the total mass of all starting materials converted into the desired product in the balanced equation.

Question 8

How do you work out atom economy?

Answer 8

Mass of desired product
——————————- x100
Total mass of reactants

Question 9

What is the relationship between atom economy and % yield?

Answer 9

Reactions which have a high percentage yield may have a low atom economy value if
large quantities of by-products are formed.