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How to balance chemical equations
The Mole and Avogadro's Number
How to work out empirical formula of a compound from its % mass composition
Step by step how to do basic chemical calculation
Chemical calculation involving concentration of solution
Take note the two formulae used in this example which are:
1. Concentration (in mol/dm3) = Number of moles of solute ÷ Volume (in dm3)
OR Number of moles of solute = Concentration (in mol/dm3) X Volume (in dm3)
2. Number of moles of a substance = Mass ÷ Molar mass
OR Mass of a substance = Number of moles X Molar mass
1. Concentration (in mol/dm3) = Number of moles of solute ÷ Volume (in dm3)
OR Number of moles of solute = Concentration (in mol/dm3) X Volume (in dm3)
2. Number of moles of a substance = Mass ÷ Molar mass
OR Mass of a substance = Number of moles X Molar mass
Chemical calculation involving volume of gas
Take note the two formulae used in this example:
1. Number of moles of a substance = Mass ÷ Molar mass
OR Mass of a substance = Number of moles X Molar mass
2. Number of moles = Volume of gas ÷ Molar volume (24 dm3 at room temperature and pressure, rtp)
OR Volume of gas = Number of moles X Molar Volume (24 dm3 at rtp)
1. Number of moles of a substance = Mass ÷ Molar mass
OR Mass of a substance = Number of moles X Molar mass
2. Number of moles = Volume of gas ÷ Molar volume (24 dm3 at room temperature and pressure, rtp)
OR Volume of gas = Number of moles X Molar Volume (24 dm3 at rtp)