Chemistry

• • Matter is anything that has mass and takes up space.
  • All matter consists of many small particles which are constantly moving.(The particle theory).
• Solid

  Arrangement of particles - Regular arrangement

  Movement of particles - Vibrate but stay in a fixed shape

  Closeness of particles - Very close
• Liquid

  Arrangement of particles - Randomly Arranged

  Movement of particles - Move around each other

  Closeness of particles - Close
• Gas

  Arrangement of particles-Randomly Arranged

  Movement of particles-Move quickly in all directions.

  Closeness of particles- Far apart
• The particles in gases have the most amount of energy
• The particles in solids have the least amount of energy.
• Physical Changes

  • A substance undergoes a physical change when it has a new form (e.g shape or size)but no new substance is formed.
  • It is usually reversible.
• Chemical Changes

  • A chemical change is when one or more new substances are formed.
  • It is not reversible
  • It involves breaking and forming new bonds between atoms and therefore requires energy( or it sometimes releases energy)
• Identifying a chemical change

  • New substances are formed
  • There is a colour change
  • Bubbles of gas form
  • a new solid(precipitate) forms
• Element Formulas

  • Every Element starts with a capital letter
  • The number is how many atoms
• Elements only have one type of atom.

  Compounds have two or more types of atoms.

  Mixtures have two or more types of elements or mixtures.
• • All substances are made from tiny particles called atoms.
  • An atom is the smallest part of an element that can exist.
  • An element is a substance made up of only one type of atom.
  • Some elements exist as 2 or more of the SAME atoms bonded together
  • A molecule is 2 or more atoms bonded together(Can be an element or compound).
• Pure Substances

  • A pure substance has a constant composition
  • Al elements and compounds are pure substances.
• Atom - The smallest particle or "Building block" of a substance.

  Element - A substance made up of only one type of atom.
• For Example:

  A piece of pure carbon is only made up of carbon atoms. This piece of pure carbon is a sample of the element carbon.
• Periodic Table explained

  A) Atomic Number

  B) Atomic Mass

  C) Name

  D) Symbol

  
• • There are 118 Known elements, but only 98 of these occur naturally, the rest are man made.
• • There are 118 known elements, but only 98 of these occur naturally, the rest are man made.
  • Each element has its own chemical symbol
  • The same set of chemical symbols are used world wide
  • Elements are displayed in the periodic table(From lightest to heaviest because each has an extra proton and electron.)
  • It is divided into metals, non-metals and metalloids
  • The rows are called periods
  • The columns are called groups
  • Each group has the same number of electrons in their outer shell
  • Each period has the same number of electron shells