module 2: 3.4 reacting quantities Flashcards
reacting quantities 2.1.3
1
Q
define theoretical yield
A
the maximum possible amount of product that can be produced
2
Q
why is the theoretical yield difficult to achieve
A
- the reaction may not have gone to completion
- other reactions (side reactions) may have taken place alongside the main reaction
- purification of the product may have resulted in the loss of some product
3
Q
how do you calculate percentage yield
A
percentage yield = actual yield / theoretical yield * 100
4
Q
define limiting reagent
A
the reactant that is not in excess will be completely used up first and stop the reaction
5
Q
define atom economy
A
the atom economy of a chemical reaction is a measure of how well atoms have been utilised
6
Q
how is a high atom economy formed
A
- produce a large portion of desired products and few unwanted products
- are important for sustainability as they make the best use of natural resources
7
Q
how do you calculate atom economy
A
atom economy = sum of molar masses of desired products / sum of molar masses of all products * 100
