m. rahman c1 topic 4 1) why are gold and platinum found in the ground as uncombined elements?...
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M. Rahman C1 TOPIC 4 3) The process by which iron extracted from iron oxide on an industrial scale is? a) Electrolysis b) Reduction by carbon Answers Reduction by carbon Bonus: Why Expert answer; Below carbon in reactivity series so does not require electrolysis. Avoid electrolysis when possible because requires a lot of energy and is expensiveTRANSCRIPT
M. RahmanC1 TOPIC 4
1) Why are gold and platinum found in the ground as uncombined elements?
Answers
Unreactive-don’t react with oxygen.
M. RahmanC1 TOPIC 4
2) A rock which contains enough metal to be economically viable to extract is called…
Answers
Ore
M. RahmanC1 TOPIC 4
3) The process by which iron extracted from iron oxide on an industrial scale is?a) Electrolysisb) Reduction by carbon
AnswersReduction by carbon
Bonus: WhyExpert answer;Below carbon in reactivity series so does not require electrolysis. Avoid electrolysis when possible because requires a lot of energy and is expensive
M. RahmanC1 TOPIC 4
4) Reactive metals in rocks are mainly found with …a) Chlorineb) Oxygenc) Carbon dioxide
Answers
b) Oxygen
M. RahmanC1 TOPIC 4
5) Name two metals found uncombined in the earth crust
Answer Any two from• Gold, silver, platinum
M. RahmanC1 TOPIC 4
6) Why are some metals found uncombined?
Answer Unreactive
M. RahmanC1 TOPIC 4
7) Reduction is….
Answer Loss of oxygen
M. RahmanC1 TOPIC 4
8) Oxidation is …..
Answer gain of oxygen
M. RahmanC1 TOPIC 4
9) What are the two methods of extracting metals from their ore…
Answer • Electrolysis• Heating with carbon (reduction)
M. RahmanC1 TOPIC 4
10) What determines the method used for extraction of metals.a) Reactivityb) Conductivityc) How strong it is
Answer a) Reactivity.
M. RahmanC1 TOPIC 4
11) Which of the following metals are extracted using Electrolysis.a) Aluminiumb) Copperc) Iron
Answer a) Aluminium
M. RahmanC1 TOPIC 4
12) Why is aluminium not extracted by heating with carbon?
Answer • Aluminium above carbon in reactivity series.• So carbon cannot take an oxygen away
from a metal (aluminium) which is more reactive
M. RahmanC1 TOPIC 4
13) Why would you not use electrolysis to extract iron.
Answer • Electrolysis uses a lot of energy and
more expensive.• No need to use it when it is not
required
M. RahmanC1 TOPIC 4
14) Which of the following metals are the most reactive.a) Platinumb) Potassiumc) Zinc
Answer a) Potassium
M. RahmanC1 TOPIC 4
15) Give three properties of metals (3).
Answer a) Strongb) Malleablec) Good conductor of heat and electricity
M. RahmanC1 TOPIC 4
16) Why is aluminium used for aeroplanes (2)
Answer Low densityCorrosion resistance.
M. RahmanC1 TOPIC 4
17) Why is copper used for electrical cables (2).
Answer Good conductor of electricity.Has high melting point.
M. RahmanC1 TOPIC 4
18) Why is copper used for pipes in plumbing (2).
Answer Does not react with water-so no corrosion.
M. RahmanC1 TOPIC 4
19) Why are gold and silver used for Jewellery
Answer a) Soft-so can be easily shapedb) Shiny-looks good.
M. RahmanC1 TOPIC 4
20) Why are gold and silver used for Jewellery
Answer a) Soft-so can be easily shapedb) Shiny-looks good.
M. RahmanC1 TOPIC 4
21) Describe the structure of metals (3).• Regular arrangement of identical atoms.• The layers of atoms can slide over each other, • which makes them malleable and easily shaped
M. RahmanC1 TOPIC 4
22) How can metals like iron be made stronger?
Answer Convert into an alloy
M. RahmanC1 TOPIC 4
23) Define an alloy.
Answer A mixture of two or more metals or a metal and non- metal.
M. RahmanC1 TOPIC 4
24) Explain why alloys are strong?
Answer • Alloys are made up of atoms of
different sizes.• This upsets the layers.• The layers cannot slide past each
other, making alloys harder.
M. RahmanC1 TOPIC 4
25) Give an example of smart alloy, describing its properties.
Answer • Nitinol-shape memory alloy.• It is an alloy of nickel and
titanium.• If you bend it, it will go back to
its original shape when heated.
M. RahmanC1 TOPIC 4
26) Give at least three advantages of recycling metals.Answer 1) There is a limited amount of metals in the
earth-recycling conserves that.2) Saves energy, since mining and extraction
require huge amounts of energy3) Costs less because energy costs money.4) Reduces the amount of rubbish that goes into
landfills.5) Less pollution because less fossil fuels burnt
to provide energy.
M. RahmanC1 TOPIC 4
27) Give one disadvantages of recycling metals.
Answer Recycling is not free- cost involved in collecting, transporting sorting and processing metals