Chemistry - Form 3

• Matter is anything that has mass and takes up space.
• The 3 states of matter are solid, liquid and gas.
• Non-Matter does not have mass and does not occupy space.
• Living Matter show all signs of life.
• Non-Matter was never alive and never showed signs of life.
• THE PARTICULATE THEORY OF MATTER

  1. All matter is made up of particles.
  2. The particles are in constant motion and temperature affects their speed of motion.
  3. The particles have empty spaces between them.
  4. The particles have forces of attraction between them.
• DIFFUSION

  The movement of particles from an area of high concentration to an area of lower concentration until the particles are evenly distributed.
• Osmosis

  The overall movement of water molecules through a selectively permeable membrane from where the water is at a high concentration to where it is at a lower concentration
• Sublimation


  When anything solid turns into a gas without first becoming liquid
• Atoms that can exist by themselves are those found in group zero (also known as group 8)
• Atoms in group 8 are stable and unreactive because they have a full outermost shell
• Outermost shells

  Also known as valence electrons
• Helium has a full outermost shell (in group 8)
• Atoms that do not have full outer shells are not stable
• Atoms attempt to gain full valence (outermost) shells and become stable by bonding with each other to achieve a noble gas (group 8) configuration (full outermost shell)
• Ways atoms can achieve a full outermost shell

  1. Using valence electrons to atoms of another element

  2. Gaining valence electrons from atoms of another element

  3. Sharing electrons in their valence electrons with other atoms
• Types of chemical bonding

  • Ionic Bonding
  • Covalent Bonding
  • Metallic Bonding
• Ionic Bonding

  Involves the transfer of valence electrons from metal atoms to non-metal atoms
• Ionic Bonding

  • Metals are found to the left of the periodic table and must have 1, 2, or 3 valence electrons
  • Non-metals are found to the right of the periodic table and most have 5, 6, or 7 valence electrons
  • When an atom loses or gains electrons, it forms an ion
  • Cations have more protons than electrons and a positive charge
  • Anions have more electrons than protons and a negative charge
• Covalent Bonding

  Involves the sharing of valence electrons between non-metal atoms
• Covalent Bonding

  • Non-metals are found on the right-hand side of the periodic table and have 4, 5,6, or 7 valence electrons
  • Atoms achieve a full outer shell by sharing electron pairs between overlapping outermost shells
  • Shared pairs of electrons form covalent bonds and are known as bonding pairs
  • Two or more non-metal atoms can bond together by sharing electron pairs to form molecules
• The pattern of electrons' arrangement is known as the electronic configuration
• Examples of noble gases

  • Argon
  • Krypton
  • Neon
  • Helium
• Noble gases are also called inert gases because they are very unreactive and stable
• Metallic bonding

  Metal atoms are packed tightly together in rows to form a metal lattice and their valence electrons become delocalized, forming positive cations and a sea of mobile electrons
• Isotope is the same atomic number