periodic table

• elements in the same group of the periodic table have the same number of electrons in their outershells
• elements in the period(row) have the same number of electron shells
• why was newlands periodic table incomplete?

  many of the periods were unknown and was arranged in order of atomic weight so they were placed in incorrect groups
• what did mendeleev do?

  arranged elements in columns based on similar properties and atomic weight but left gaps for the undiscovered ones
• what are metals?


  elements react to form positive ions
• what are non-metals?


  elements that react to form negative ions
• what is group 0?

  Noble gases
• features of noble gases?

  • have full outer shell of electrons
  • unreactive
  • do not form molecules
• why are group 0 elements unreactive?

  they have a full outer shell of electrons
• how does the BP of the group 0 elements change down the group?

  BP increases
• what are group 1 metals?

  alkali metals
• properties of group 1 elements

  • have 1 electron in their outershell
  • react with O2,CL2, H20
• How does the reactivity of group 1 elements change down the group?

  reactivity increases down group 1
• why does the reactivity of group 1 elements increase down the group?

  • atoms increase in size
  • more shells so outer shell is further away from the nucleus
  • electrostatic attraction between the nucleus and the outer electron is weaker
• how do group 1 reacts with oxygen?

  metal + oxygen ----> metal oxide
• how do group 1 reacts with water?

  metal + water----> metal hydroxide + hydrogen

  e.g. sodium + water----> sodium hydroxide + hydrogen
• what is observed when group 1 metals react with water?

  • fizzing= formation of h2 gas
  • solid disappears= metal gets used up
• how do group 1 reacts with chlorine?

  metal+chlorine-----> metal chloride
• what are group 7 elements?

  halogens
• properties of group 7 elements?

  • 7 electrons in their outer shell
  • non metals
  • all are diatomic molecules(F2 CL2 BR2)
• How does the reactivity of the group 7 elements change down the group?

  Decreases
• why does the reactivity of the group 7 elements decrease down the group?

  • increase in size
  • more shells so outer shell is further away from the nucleus
  • electrostatic attraction between nucleus and outershell is weaker
  • harder to gain an electron to fill outer shell
• the melting and boiling point of group 7 halogens increase as you go down the group
• why does the m/b point of the group 7 elements increase down the group?

  • molecules increase in size
  • intermolecular forces become stronger
  • more energy required to overcome the forces of attraction
• what is fluorine in room temp?

  gas
• what is chlorine in room temp?


  gas
• what state is bromine in room temp?

  liquid
• what is iodine in room temp?

  solid
• what colour is fluorine in room temp?

  yellow
• what colour is chlorine in room temp?

  yellow- green
• what colour is bromine in room temp?


  red-brown
• what colour is iodine in room temp?

  grey
• halogens react with metals to produce salts
• when halogens react with non metal they form a halide ion
• what is a displacement reaction?


  A chemical reaction where one element is replaced by another element in a compound.
• WHICH HAS THE HIGHEST MELTING POINT? TRANSITION OR GROUP 1 METALS?

  TRANSITION
• WHICH ONE HAS THE HIGHEST DENSITY?TRANSITION OR GROUP 1 METALS?

  TRANSITION
• WHICH HAS THE HIGHEST STRENGTH? TRANSITION OR GROUP 1 METALS?

  TRANSITION
• WHICH HAS THE HIGHEST HARDNESS? TRANSITION OR GROUP 1 METALS?

  TRANSITION
• WHICH REACTS EASILY WITH O2, H20, HALOGENS? TRANSITION OR GROUP 1 METALS?

  Group 1 metals