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This revision guide covers reactions of metals, extraction methods, corrosion, protection mechanisms, electrochemistry, and more. Includes summaries, definitions, and practical examples for effective study.
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The following slides should help you with your revision, but should not be your only form of revision. Remember to use your notes, a textbook, websites and Past Papers to help you. You can also ask a chemistry teacher for help too.
Complete the Summary of Reactions of Metals Dangerously Reactive forms metal oxide. Reacts with cold water to form metal hydroxide + H2 Reacts explosively Reacts form metal salt + H2O Reacts with steam to form metal hydroxide + H2
Complete the Summary of Reactions of Metals Slowly forms metal oxide on heating No reaction No reaction No Reaction
Revise the Reactivity Series MetalRhyme Potassium Please Sodium Send Lithium Little Calcium Charlie Magnesium McLean Aluminium A Zinc Zebra Iron If Tin The Lead Lazy Hydrogen Horse Copper Can’t Mercury Munch Silver Soft Gold Grass Platinum Properly.
Complete the summary of the Extraction of Metals…..Breaking Compounds Electrolysis of molten ore Heat with reducing agent: C/CO/ CO2/H2
What’s happening in the extraction of metals reactions? • To reduce a metal oxide to its metal requires the same amount of energy as the metal released to form the bonds in the oxide, since the same bonds are being broken as were made. • Metal oxides low in the activity series require only small amounts of energy to break the bonds, heat alone. This is because the oxides didn’t readily form in the first place; the metal is more stable on its own. ………………………………………………………..……………………..continued
What’s happening in the extraction of metals reactions? • Metal oxides high in the activity series require lots of energy to break the bonds, heat and electricity. This is because the oxides formed readily; the metals are more stable as oxides than as metals on their own. • Metals in the middle of the Activity Series tend to need coaxing both to form the oxide and to breakdown the oxide. Carbon, carbon monoxide or hydrogen can be used to help coax the metal oxide in the middle of the Activity Series to breakdown to form their metal.
What is Corrosion? • A chemical reaction which involves the surface of a metal changing from an element to a compound.
What is Rusting? • The special name given to the corrosion of iron.
What is required for corrosion? • Water and oxygen to be in contact with the surface of the metal.
What is the test for rust? • Ferroxyl indicator turns blue.
Name the two types of protection against corrosion • Physical protection • Sacrificial protection
Give 4 examples of physical protection • Painting • Greasing or oiling • Coating with plastic • Coating with other metals
What is required for sacrificial protection of a metal? • A more reactive metal is attached to the metal to prevent it from corroding
To make many household appliances work a supply of electricity is needed, name the two forms the supply normally comes in? Mains electricity Batteries ( More accurately …cells)
What happens in an electrical wire when electricity is passed along? There is a flow of electrons along the wire.
How can the voltage in electrochemical cell be made as large as possible? • The further apart the metals are from each other in the Electrochemical Series ( Check the Data Book!!) the greater the voltage produced.
Which pair of metals would give the largest volume? • Mercury and silver • Aluminium and magnesium • Zinc and iron • Lead and Calcium • Lead and Calcium
What is the purpose of the electrolyte in an electrochemical cell? • The purpose of the electrolyte in the cell is to complete the circuit by enabling ions to carry the charge in the internal circuit.
What is the definition of an electrolyte? • An electrolyte is a solution or paste which allows electricity to move through it.
What types of solutions make good electrolytes? • Ionic solutions.
Why do ionic solutions make good electrolytes? • Ionic solutions make good electrolytes because the ions are free to move.
Which direction do electrons flow in an electrochemical cell? • Electrons always flow from the metal higher to the metal lower in the Electrochemical Series, via the external circuit.
What is the definition of a displacement reaction? • A more reactive metal will displace a less reactive metal from a solution of its ions.
Complete the Results for these Displacement Reactions: Conclusion: A more reactive metal displaces a less reactive metal from a solution of its ions.
Zinc is added to copper (II) sulphate solution, what happens? Zn Zn Zn Cu2+SO42- Zn2+SO42- SO42- Cu2+SO42- Zn2+ Cu2+SO42- Cu SO42- Cu Brown solid (Cu ) appears. Zn atoms go into solution, blue colour becomes paler.
What is the definition of an alloy? An alloy is a mixture of metals or of metals with non-metals.