C3.3 and C3.4 (types of chemical reactions+electrolysis)

Cards (65)

  • what is a redox reaction?
    a reaction where reduction and oxidation happen at the same time
  • what is reduction in terms of transfer of oxygen?
    reduction is the loss of oxygen from a substance
  • what is oxidation in terms of transfer of oxygen?
    Oxidation is the gain of oxygen by a substance
  • what happens when aluminium gains oxygen?

    It is oxidised to aluminium oxide
  • What happens when iron oxide loses oxygen?
    it is reduced to iron
  • what is a reducing agent?
    The agent that reduces a substance originally with oxygen to end up without oxygen
  • what is an oxidising agent?
    an agent that oxidises a substance originally without oxygen to end up with oxygen
  • what does oil rig stand for?
    Oxidation is loss of electrons, reduction is gain of electrons
  • what does a half equation show?
    The change that happens to one reactant in a reaction
  • what is reduction in terms of electrons?
    Gain of electrons
  • what is oxidation in terms of electrons?
    loss of electrons
  • what is an acid?
    A substance that releases hydrogen ions when it dissolves in water to make an aqueous solution
  • what makes a solution acidic?
    Hydrogen ions
  • what is a base?
    Usually a metal oxide or metal hydroxide that can neutralise acids
  • what can also be the name of a base that can dissolve in water?

    could also be an alkali
  • what does an alkali release when dissolved in water?
    Hydroxide ions
  • what does it mean if the pH is less than 7?

    Acidic
  • what does it mean if the pH is equal to 7?

    Neutral
  • what does it mean if the pH is more than 7?

    Alkaline
  • how do you work out the pH of a solution?

    Using universal indicator or a pH meter
  • What colour normally represents acidic?

    Red
  • what colour normally means neutral?

    green
  • what colour normally means alkaline?

    Blue
  • what is neutralisation?

    The reaction between an acid and a base or an alkali to form a salt and water
  • what is the equation for an acid + a base?

    Acid + base --> salt + water
  • what happens to the pH when a base or alkali is added to and acid?

    Increases
  • what happens to the pH if an acid is added to a base or an alkali?

    Decreases
  • how can you predict the salt made in a neutralisation reaction?

    The first part comes from the metal in the base or in the alkali
    The second part comes from the acid used
  • what happens when an acidic solution and an alkaline solution react together?
    It produces water
    The ionic equation is H+ + OH- -> H2O
  • what are carbonates?

    Ionic compounds that contain the carbonate ion CO3 2-
  • what do carbonates reacting with acids form?

    Salt, water, and carbon dioxide
  • true or false = most carbonates are insoluble in water
    True
  • what carbonates are soluble in water?
    Group 1 carbonates, sodium carbonate and ammonium carbonate
  • what does an acid + metal make?

    Salt + hydrogen
  • what does a dilute acid mean?

    It contains a low ratio of acid to volume of solution
  • what does a concentrated acid mean?

    Contains a high ratio of acid to volume of solution
  • what happens when acids release hydrogen ions?

    A covalent bond in the acid molecule breaks, producing a hydrogen ion (H+) and a negatively charged ion
  • what are weak acids in terms of ions?

    Only partially ionised which means that only a small amount of their molecules release H+ ions
  • what are strong acids in terms of ions?
    Fully ionised, all of their molecules release H+ ions
  • what sometimes happens to weak acids?

    Their reaction does not go to completion and 2 arrows in opposite directions are shown in the equation