What is empirical formular
Simplast whole number ratio of the elements present in one molecule of compound
What is molecular formula
the number and type of each atom in a molecule
What is empirical formula calculated from
the mass of an element in a compounds
Or
Percentage composition by mass of each element
How to work out empirical formula From mass
find moles using n=m/Mr
Divide by simplest ratio of moles like imagine hydro had 2 moles and carbon had 4 moles you divide by 2 moles
what is the molecular formular
the actual number of atoms of each element in a compound
H
how do you calculate the molecular formula
- from relative atomic mass of empirical
- Divide compound’s relative molecular mass by the empirical formulas mass
- Multiple the number of each atom in the empirical formula by this ratio
What is awater of crystallisation
Water molecules are chemically bounded within crystal structure
What is hydrated compound
A compounds that contains water of crystallisation
Water of crystallisation is separated from the main formula by a dot when writing the chemical formula of hydrated salts
What is an anhydrous compound
a compound without a water of crystallisation
How to get from hydrated to anyhydrous
hy heating the hydrated salt
Process is reversed by adding water which reforms the hydrated compound
How can degree of hydration be calculated from experimental results
the mass of the hydrated salt must be measured before heating
The salt is then heated until it reaches constant mass
The two mass values could be used to calculate the number of moles of water in hydrated salt(water of crystallisation)
