p1 chem

• Atom


  Something that can't be broken down or split into its constituents or smaller bits by chemical means
• Compound


  Two or more types of atoms chemically bonded together
• Mixture


  Different types of atoms or compounds not chemically bonded together
• Chromatography


  1. Filter paper with a dot of the mixture about a centimeter above the water line

  2. Filter paper is dipped in water

  3. Water gets drawn up to paper due to capillary action

  4. Particles of the mixture get dragged with it

  5. Lighter particles end up highest on the paper
• RF value


  Retention factor, calculated as distance solute has gone up paper / distance solvent has gone
• Filtration


  1. Filter paper in a funnel

  2. Mixture put in the top

  3. Water drips through, leaving insoluble particles like sand in the filter paper
• Distillation


  1. Heat the mixture or solution

  2. Water evaporates

  3. Water re-condensed using a condenser tube

  4. Water collected, leaving solute behind
• Atom


  Has a nucleus with protons and neutrons, and electrons orbiting the outside
• Proton


  Charge of +1
• Electron

  Charge of -1
• Neutron


  No charge
• Atoms have the same number of protons and electrons when neutral
• Ion


  Atom that has lost or gained electrons, so has a net positive or negative charge
• Periodic table groups


  • Group 1 (alkali metals)
  • Group 2
  • Group 3-8
  • Group 0 (noble gases)
• Group

  Tells you how many electrons are in the outer shell
• Period


  Tells you how many shells of electrons the atom has
• Metals are to the left of the staircase on the periodic table, and are electron donors
• Non-metals are to the right of the staircase on the periodic table, and are electron acceptors
• Atomic number


  Number of protons in the nucleus
• Mass number

  Number of protons plus neutrons in the nucleus
• Electrons fill shells in the order 2, 8, 8, 2
• Ionic bonding


  Metals bond to non-metals by donating electrons, forming positive and negative ions
• Ionic compounds


  • Have high melting and boiling points
  • Are soluble in water
  • Can conduct electricity when molten or in solution
• Covalent bonding


  Non-metals bond by sharing electrons to fill their outer shells
• Simple covalent compounds


  • Methane (CH4)
  • Carbon dioxide (CO2)
• Giant covalent structures


  • Repeating covalent bonds, forming large molecules like diamond and graphite
• Metallic bonding


  Atoms form a lattice, with delocalized electrons surrounding the positive ions
• Polymer


  Long chain formed by joining many monomer molecules together
• To make a polymer, high pressure and a catalyst are needed to force the monomers together
• The periodic table was developed over time by scientists like Dalton, Newlands and Mendeleev
• Oxidation


  Metal + oxygen -> metal oxide
• Acid + metal hydroxide

  • > salt + water (neutralization)
• Thermal decomposition


  Heat breaks down a compound
• Displacement


  More reactive metal displaces less reactive metal from a compound
• Rust is iron oxide formed when iron reacts with oxygen or water
• Extracting iron from iron ore

  Use a blast furnace with coke (carbon) to reduce the iron carbonate
• Relative atomic/formula mass


  Mass of an atom or molecule relative to the mass of a carbon-12 atom
• In chemical reactions, atoms are not created or destroyed, so reactions must be balanced
• Balancing chemical equations


  1. Start with complex molecules

  2. End on elements

  3. Multiply symbols to balance chlorines

  4. Multiply H2 on right to balance hydrogens
• Relative atomic mass


  Mass number of an element, tells you how many grams a mole of that element weighs