Matter: Periodic table and elements

• The Periodic Table


  A table that organises the chemical elements based on their properties
• The Periodic Table


  • Periods
  • Groups
  • Metals
  • Non-metals
• Properties of metals


  Chemical properties of metal oxides with respect to acidity
• Properties of non-metals


  Chemical properties of non-metal oxides with respect to acidity
• Key terms


  • Elements
  • Molecules
  • Compounds
  • Mixtures
  • Chemical/Physical Reactions
  • Alkali Metals
  • Halogens
  • Noble Gases
  • Trend
  • Periods
• What is are elements?

  What all substances are made up of, and which contain only one type of atom
• What is an atom?

  The smallest particle of an element that can exist
• Molecules


  Two to thousands of atoms joined together. Most non-metals exist either as small or giant molecules
• Compound


  Pure substances made up of two or more elements strongly joined together
• Chemical formula


  Shows the elements present in a compound and their relative proportions
• Polymer


  A molecule made of thousands of smaller molecules in a repeating pattern. Plastics are man-made polymers, starch is a natural polymer
• Chemical symbols:

  • hydrogen
  • oxygen
  • nitrogen
  • carbon
  • iron
  • zinc
  • copper
  • sulfur
  • aluminium
  • iodine
  • bromine
  • chlorine
  • sodium
  • potassium
  • magnesium
• Noble Gases


  • Generally exist as single atoms
  • Don't naturally react with other substances
  • Were one of the last groups of elements to be discovered
• Noble Gases


  • Helium (He)
  • Neon (Ne)
  • Argon (Ar)
  • Krypton (Kr)
  • Xenon (Xe)
• Melting point


  The temperature at which a substance changes from a solid to a liquid state
• Helium was first discovered in the Sun in 1869
• It wasn't until 1905, when argon was isolated, that scientists realised there was a whole group of elements missing from the periodic table
• Compounds made from noble gases


  • Xenon hexafluoride
  • Xenon difluoride (XeF2)
• Noble gases don't form any lattice structures like sodium chloride
• What are the rows in the periodic table called?

  Periods
• What are the columns in the periodic tables called?

  groups
• Which scientist first published the periodic table based on the properties of the elements?

  Dmitri Mendeleev
• Where are the alkali metals located on the periodic table?


  The first group (column)
• Give the names of 3 alkali metals?

  • Lithium (Li)
  • Sodium (Na)
  • Potassium (K)
• How does the reactivity of the alkali metals change down the group?


  increased reactivity
• Where are the transition metals located on the periodic table?


  Transition metals are foundin the d-blockof the periodic table.
• Give the names of three transition metals

  1. Iron
  2. Nickel
  3. Colbalt
• Which scientist first described elements in terms of their atomic number?

  Dmitri Mendeleev
• Name 3 halogens


  1. Flourine
  2. Chlorine
  3. Bromine
• Where are metals located on the periodic table?


  Metals are on the left of the periodic table
• List 3 physical properties of metals

  • Malleability: Metals can be hammered into thin sheets without breaking.
  • Ductility: Metals can be stretched into wires.
  • Conductivity: Metals are good conductors of heat and electricity. Silver and copper are the best conductors of electricity, while lead and mercury are poor conductors.
• Name a precious metal and describe a property of a precious metal?

  Gold. They are not reactive
• What are the 4 signs that a chemical reaction has taken place?


  • colour change.
  • effervescence.
  • precipitation.
  • temperature change.
• Distinguish between a chemical and a physical change


  In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.
• What is the law of conservation of mass?


  mass is neither created nor destroyed in chemical reactions
• Where do reactants appear in an equation?


  at the beginning
• Where do products appear in an equation?

  at the end