(5) Chemical formulae, equations and calculations Flashcards
How do we find the relative formula mass?
By adding up all the relative atomic masses.
How do we use the relative formula mass to find the percentage composition?
Percentage composition= (Relative atomic mass of atom/Relative atomic mass of compound) x 100
What is a mole?
It is a unit of the amount of substance.
What is the formula for moles?
Moles= Mass/molar mass
What is an empirical formula?
It’s the formula that shows the simples whole number ratio of atoms present in a compound.
What is a molecular formula?
The actual number of atoms in each element present in a molecule.
What are the steps to find empirical formula?
1) Find the number of moles of atoms
2) Divide by the smaller number to find the ratio
How do we find the percentage yield?
Percentage yield= (Actual yield/Theoretical yield) x 100
