chem

• Metal react with oxygen to produce metal oxide
• Oxidation as the reactions cause the metal to gain oxygen
• When metals react with other substances, the metals form positive ions
• Reactivity relates to the tendancy to form a positive ion
• Non-metals hydrogen and carbon are often included in the reactivity series
• A more reactive metal can displace a less reactive metal from a compound
• In electrolysis, electricity is passed through molten salt or a solution containing dissolved salts.
• The reactivity series is used to predict which metal will be displaced by another when they both react with an acid or water
• Electrolytes conduct electrical current because their particles carry charge (positive or negative).
• The anode is where oxidation occurs (positive charge)
• Potassium, Sodium, Lithium, Calcium, Magnesium, Aluminium, Manganese, Zinc, Iron, Lead, Hydrogen, Copper, Silver, Gold
• Ionic compounds have high melting points due to strong forces of attraction between positive and negative ions.
• An electrode is a conductor that connects an external circuit to a non-conducting material such as a solid, liquid or gas.
• When two metals are placed into an electrolyte solution, one metal will corrode more easily than the other.
• A cathode is the negatively charged electrode at which reduction takes place.
• An ionic bond forms between metals and non-metals
• The reactivity series shows how reactive different elements are towards oxygen
• Most metals are found as compounds that require chemical reactions to extract the metal
• Metals less reactive than carbon can be extracted from their oxides by reduction with carbon
• If a metal is more reactive than carbon, it is oxidised to be extracted from their oxide
• O- oxidation

  I- is

  L- loss of electrons

  R- reduction

  I- is

  G- gain of electrons
• Mg(s) + Cu2+(aq) = Cu(s) + Mg2+(aq)
• Acids react with some metals to produce salts and hydrogen
• Acid + Metal = Salt + Hydrogen
• Since reduction and oxidation happen in the same reaction at the same time, it is called a redox reaction
• Acids are neutralised by alkalis like soluble metal hydroxides
• Acids are neutralised by bases like insoluble metal hydroxides and metal oxides
• Acids are neutralised to produce salts and water
• Acids are neutralised by carbonates to produce salt, water and carbon dioxide
• Acid + Metal carbonate = Salt + Water + Carbon dioxide
• Acid + Base/Alkali = Salt + Water
• Salt produced in reaction between acid + base/alkali depends on

  • The acid used
  • The positive ions in the base, alkali or carbonate
• Soluble salts can be made from acids by reacting them with insoluble substances
• Insoluble substances include: Metal, metal oxides, hydroxide or carbonates
• Solid is added to the acid until no more reacts and the excess solid is filtered off to produce a solution of the salt
• Salt solutions can be crystalised to produce solid salts
• REQUIRED PRACTICAL = Bunsen Burner to heat dilute acid

  Water bath/electrical heater to evaporate solution
• Acids produce hydrogen ions (H+) in aqueous solutions.
• Aqueous solutions of alkalis contain hydroxide ions (OH-)
• The pH scale is a measure of acidity and alkalinity of a solution