chemistry

• Solid


  • Shape - fixed
  • Volume - fixed
  • Compressibility - cannot
  • Movement - vibrates only
  • Arrangement - close together
• Liquid


  • Shape - not fixed
  • Volume - fixed
  • Compressibility - cannot
  • Movement - slides past each other
  • Arrangement - close together
• Gas

  • Shape - not fixed
  • Volume - not fixed
  • Compressibility - can
  • Movement - randomly in any direction
• Changes of matter

  1. Solid to liquid = melting

  2. Liquid to gas = evaporation/boiling

  3. Gas to liquid = condensation

  4. Liquid to solid = freezing

  5. Solid to gas / gas to solid = sublimation
• Evaporation


  • Occurs at any temperature
  • Occurs on surface of liquid
  • Occurs very slowly
• Boiling


  • Occurs at a certain temperature
  • Occurs throughout the liquid
  • Occurs rapidly
• Temperature increase


  • Particles have more energy
  • Volume of gas increases
• Pressure increase


  • Particles move closer
  • Volume of gas decreases
• Diffusion


  The random movement of particles from a higher concentrated region to a lower concentrated region
• Element


  Contains only one type of atom that cannot be further broken down
• Atom


  Smallest particle of an element that contains chemical properties of that element
• Monoatomic element


  Exists as individual atoms (1 atom)
• Molecule


  A group of two or more atoms that are chemically bonded
• Diatomic molecule


  Exists as two atoms
• Compound


  Contains two or more types of atoms that are chemically bonded
• Decomposition of compounds


  Can be done by thermal composition or electrolysis
• Mixture


  Contains more than one type of substance that can be physically separated
• Proton number


  Atomic number
• Nucleon number


  Neutron + proton
• Electron number


  Proton number
• Isotopes


  Different atoms of the same element that has the same number of protons but different number of neutrons, making them have the same chemical properties but different physical properties
• Ionic bonding


  Strong electrostatic attraction between oppositely charged ions
• Formation of ions


  Atom gains or loses electrons to reach stable electronic configuration
• Cations


  • Positively charged ions
  • Lost electrons to reach stable electronic configuration
  • Metal atoms
• Anions


  • Negatively charged ions
  • Gain electrons to reach stable electronic configuration
  • Non-metal atoms
• Formation of ionic compounds


  Metal atom transfers their outer shell electrons to non-metal atoms to reach stable electronic configuration
• Ionic compounds


  • Crystalline solid
  • High melting and boiling points
  • Good conductor of electricity in molten or aqueous states
• Giant lattice structure


  Formed by ionic compounds; the regular altering pattern of oppositely charged ions
• Covalent compounds


  Non-metal atoms shares electrons with one another through covalent bonds
• Simple molecular covalent compounds


  • Low melting and boiling points
  • Don't conduct electricity
• diamond

  • High melting and boiling point
  • Don't conduct electricity
  • Each carbon atom is chemically bonded with 4 other carbon atoms
  • Structure: tetrahedral shape
• Graphite


  • High melting and boiling point
  • Does conducts electricity
  • Each carbon atom is chemically bonded with 3 other carbon atoms
  • Structure: layer of hexagons; trigonal planar shape
• Silicon oxide


  • High melting and boiling point
  • Doesn't conduct electricity
  • Each carbon atom is chemically bonded with 4 oxygen atoms and each oxygen atom is chemically bonded with 2 silicon atoms
• Metallic bonding


  Electrostatic attraction between cations and sea of delocalised electrons
• Metals


  • Good conductor of electricity
  • Malleable and ductile
• Molecular formula


  Shows the number and types of different atoms in one molecule
• Empirical formula


  Shows the simplest ratio whole number of the different atoms/ions in a compound
• Relative atomic mass


  Average mass of the isotopes of an element compared to 1/12 of the mass of an atom of 12C
• Relative molecular mass


  Sum of relative atomic mass
• Relative formula mass


  The relative molecular mass of an ionic compound