Periodic table

• Group 1 metals are known as

  alkaline metals
• what do they form when they react with water

  Alkaline solution
• Some properties of group 1

  • They are all soft metals which can easily be cut with a knife
  • They have relatively low densities and low melting points
  • They are very reactive (they only need to lose one electron to become highly stable)
• Group 1 metals get what further down down the group 


  They get softer
• The first 3 alkali metals are

  Less dense than water
• They have all low melting points which

  decrease as you move down the group, due to decreasing attractive forces between outer electrons and positive ions
• The reactivity of the group 1

  Increases as you go down the group
• Group 7 are known as

  Halogens
• Fluorine physical state and colour

  • Yellow gas
• chlorine physical state and colour

  • Pale yellow-green gas
• Bromine physical state and colour

  • Red-brown liquid
• Iodine physical state and colour

  • Grey solid
• The melting and boiling points group 7

  increase as you go down the group
• why does the melting and boiling point increase

  • This is due to increasing intermolecular forces as the atoms become larger, so more energy is required to overcome these forces
• Covalent bonding group 7

  In each molecule, two atoms of the element are held together by a single covalent bond.
• What is covalent bonding 


   A chemical bond formed when electrons are shared between two atoms.
• All group 7 elements are 


  Diatonic
• Potassium


  Reaction with water: violent lilac flame
• Sodium


  Reaction with water: very quick orange flame
• Lithium


  Reaction with water: quick, colourless
• Calcium


  Reaction with dilute acid: more slow, no flame
• Magnesium


  Reaction with dilute acid: very quick
• Zinc


  Reaction with dilute acid: fairly slow
• Iron


  Reaction with dilute acid: more slow
• Copper


  Reaction with dilute acid: very slow
• Why does the reactivity increase in group 1 as you go down

  because the atoms are further away from the nucleus’s and the attraction between the nucleus and outer electron gets weaker so the electron is easily lost