periodic table

• definition of ionisation energy?


  the energy needed to remove 1 mole of electrons from 1 mole of gaseous atoms
• oxygen ionisation energy equation?

  Oxygen ionization energy equation: O(g) -> O+(g) + e-
• factors affecting ionisation energy?

  nuclear charge , atomic radius , shielding
• what is the trend in ionisation energy down a group?

  Decreases
• what is the trend in ionisation energy across a period?

  Increasing
• reactivity ....... down group 2?

  increases
• what ions do group 2 produce?

  2+
• group 2 + water?

  metal + water =metal hydroxide + hydrogen
• group 2 + oxygen?

  metal + oxygen = white oxides
• group 2 + acid?

  metal + acid = salt + hydrogen
• ionic equation for neutralisation ?

  H+ + OH- -> H2O(l)
• halogens get ....... reactive as you go down ?

  less
• halogen initial colour?


  f2= yellow

  cl2=green

  br2=red-brown

  i2=grey
• silver nitrate precipitate colours?


  cl2= white

  br2= cream

  i2 = yellow
• equation for bleach?

  2NaOH + cl2 = NaClO + NaCl + H2O
• test for carbonates?

  add acid to sample if co2 is released carbonates are present
• test for sulfates?

  add HCl and BaCl2 if there is a white precipitate then sulfates are present
• test for halides?

  silver nitrate and then look at precipitate colour to decide which halide
• test for ammonium?

  heat sample and hold red litmus paper over tube , turns blue if ammonium is present
• ideal test order?


  carbonates , sulfates , halides
• what groups are in the s block?

  1 and 2
• what is the d block?

  transition metals
• what groups are in the p block?

  3-8
• what effect does shielding have on ionisation ?


  more electron shells means less energy required due to weaker attraction
• what effect does nuclear charge have on ionisation ?

  more protons means bigger attraction needing more energy
• what effect does atomic size have on ionisation?

  bigger atoms means more distance from nucleus making it easier to remove outer electrons
• what is the decrease at aluminium for ionisation due to?

  sub-shells
• what is the decrease at sulphur in ionisation due to?

  electron repulsions in orbitals