- Created by: Marainesthai
- Created on: 26-10-17 20:24
C4 Chemical calculations
What is Ar?
It is the mean relative mass in grams of isotopes of an element compared to carbon-12.
What is a mole?
Moles are relative atomic masses in grams.
The formula for the number of moles
number of moles = mass / Ar or Mr
What do symbol equations tell you?
Symbol equations tell you the number of moles of a substance involved in a reaction.
They can be deduced from the masses of chemicals involved and the ratio of the number of moles.
What is a limiting reactant?
It is a reactant used up first not in excess.
What is percentage yield?
It compares masses of products the reaction makes with the theoretical mass made.
Percentage yield formula
percentage yield = actual mass made / maximum theoretical product mass possible
Factors affecting percentage…