chemistry g8

• elements and compounds
• a compound is made up from two or more elements chemically bonded together
• the periodic table shows the properties of all known elements, arranged by atomic number (protons) and mass number (protons + neutrons)
• an element is a substance that cannot be broken down into simpler substances by chemical reactions
• the periodic table shows the properties of all known elements, arranged according to their atomic number (number of protons)
• metals are found on the left hand side of the periodic table
• noble gases are at the bottom of the periodic table
• non-metals are on the right hand side of the periodic table
• homogeneous and heterogeneous
• elements with similar properties lie in vertical columns called groups
• elements with similar properties have similar numbers of electrons in their outer shells
• a compound is made up of two or more different elements chemically combined together
• a homogenous mixture has one phase - liquid or gas
• Proving triangle congruence