structure and bonding

• protons have a mass of 1 and a charge of +1
• neutrons have a mass of 1 and a charge of 0
• electrons have a mass of almost 0 and a charge of -1
• an isotope is an atom of the same element with the same number of protons but a different number of neutrons
• copper and silver nitrate solution makes metal crystals
• metallic bonding is the electrostatic attraction between positive metal ions and delocalised electrons
• metals conduct electricity because they have free electrons that can move around the metal lattice
• metals bend easily because they consist of layers of ions that can slide over one another when the metal is bent, hammered or pressed
• metals have high melting points because a lot of energy is needed to overcome the strong bonds between the atoms
• ionic bonding is the electrostatic attraction between oppositely charged ions
• oxidation is loss of electrons and reduction is gain of electrons
• covalent bonding is the electrostatic attraction between 2 nuclei and shared pairs of electrons
• most substances that contain simple molecules have low melting and boiling points and are therefore liquids or gases at room temperature
• an allotrope is a different form of the same element