Presentation on theme: "Metals and their Properties Metals have distinctive properties such as: 1. Electrical Conductivity 2. Good Thermal Conductivity 3. Strength 4. Malleability."— Presentation transcript:
Metals and their Properties Metals have distinctive properties such as: 1. Electrical Conductivity 2. Good Thermal Conductivity 3. Strength 4. Malleability.
Reaction of Metals With Oxygen: All metals react with Oxygen. The more reactive the metal the quicker the reaction. In the Lab the Oxygen is produced by heating Potassium(v)Manganate. The Brighter the glow the more the reactive the metal. Less reactive metals produce a duller glow General Equation : Metal + OxygenMetal Oxide
Metals + Oxygen (contd) Potassium (v)Manganate acts as a source of Oxygen when Heated Mg metal is placed between two pieces of ceramic wool The more active the metal the brighter the glow
Reactions of Metals With Water: Only Metals above Hydrogen in the Activity Series react with water. In fact only the first three react with Cold water. The remaining metals above Hydrogen must be treated with Steam before a reaction will take place. General Equation: Metal + H 2 OMetal Hydroxide + H 2
Reactions of Metals With Acids: Only Metals above Hydrogen in the Activity Series react with Acids. General Equation: Metal + Acid Salt + Hydrogen
Metals and Acid(contd). Pop Pop When a metal is reacted with an Acid it produces H 2 gas which burns with a POP!
Alloys An Alloy is a mixture of metals or metals and other elements. Alloys are made to change the properties of the metal e.g.to make them harder, more pleasing on the eye or to make them more resistant to Corrosion. Examples are: Brass(a mixture of Cu&Zn), Gold (Au&Cu.The greater the proportion of Cu the lower the no.of carats),Stainless Steel (Fe,Ni&Cr)
Metal Ores Most metals are found combined to other elements such as, Oxygen and Sulphur in the earths crust.These are called Metal Ores. Only Gold, Silver and Platinum are found uncombined. As a result metals must be mined and then separated from their Ores by Metal Extraction
Extraction of Metals from their Ores Metals low down in the Electrochemical Series form weak bonds with other elements. As a result Ores of these metals can broken up easily to obtain the metal. Ores of metals high up in the Electrochemical series contain stronger bonds and therefore require more sophisticated and expensive methods of Extraction
Electrochemical Series Potassium Sodium Calcium Magnesium Aluminium Zinc Iron Nickel Tin Lead HYDROGEN Copper Mercury Stealing Gold Plates Can be Broken by Heat alone Separated from ore by Heating with CHARCOAL, thus releasing CARBON DIOXIDE. Must be Electrolysed to release Metal from Ore