Atomic Structure

1.1 ATOMS

• All substances are made of atoms.
• The periodic table lists all of the chemical elements, with eight main groups, each containing elements with similar chemical properties.
• Elements are made of only one type of atom.
• Compounds contain more than one type of element.
• An atom has a tiny nucleus at its centre, surrounded by electrons in shells.

1.2 CHEMICAL EQUATIONS

• No new atoms are ever created or destroyed in a chemical reaction.
• The total mass of reactants always equals the amount of products (Law of Conservation of Mass)
• There is the same number of each type of atom on each side of a balanced symbol equation.
• State symbols give extra information in balanced symbol equations.
• (s) = solids
• (l) = liquids
• (aq) = aqueous solutions
• (g) = gases

1.3 SEPARATING MIXTURES

• A mixture is made up of two or more substances that are not chemically combined.
• Mixtures can be separated by physical means, such as filtration, crystallisation, and simple distillation.

1.4 FRACTIONAL DISTILLATION AND PAPER CHROMATOGRAPHY

• Fractional distillation is effective in order to separate miscible liquids, using something called a fractionating column.
• This separation is possible…