Moles and water of crystallization (Moles (Empirical formulae (The…
Moles and water of crystallization
The mole is defined as the amount of a substance that contains as many particles of that substance as there are atoms in exactly 12 grams of carbon 12
1 mole contains the Avogadro number of particles. 6.02x10 to the power of 23
Amount of substance (in moles)= Mass of substance in grams / Molar mass in g mol-1
Moles in gas
The ideal gas equation is PV=nRT. rearranged for moles it is n=PV/RT.
Moles in solution
Number of moles= concentration x volume
Molar mass is the convenient way of linking moles with the mass of any chemical substance
The empirical formulae is the simplest whole-number ratio of atoms in each compound
It is important for substances that do not exist as molecules like metals and some non metals
Because these form giant crystalline structures of atoms or ions the number goes into the billions of billions which is why it is put into a simple ratio
Moles are required to work out the empirical formulae as to find the ratio you need to divide all of the moles by the smallest molar value.
The molar gas volume Vm is the volume per mole of gas molecules at a stated temperature and pressure.
Many coloured crystals are hydrated as water molecules are part of their crystalline structure, this is know as water of crystallisation
Water isn't bonded to the salt but associated with it this is represented by the dot in between the the salt and the water. for example CuSO4.5H2O
To make sure the most amount of water has been removed you can reheat the salt over and over to make sure it the most anhydrous therefore the most accurate