Topic 4: Metals and the Reactivate Series Flashcards
(84 cards)
1
Q
What is a spectator atom?
A
-Atom or element that does nothing in reaction, is the same as it went in.
2
Q
What is the shielding effect?
A
- Electrons closer to molecules are more strongly attracted then those further away.
- Inner electrons shield outer electrons from forces of attraction from the nucleus.
3
Q
When a halogen is reduced?
A
-It gains an electron and forms a Halide.
4
Q
What will happen when a more reactive halogen is added to a metal halide?
A
-The reactive halogen will displace the less reactive halogen to form a new metal halide.
5
Q
Ions in a reaction that are neither oxidized nor reduced are called?
A
-Spectator IONS.
6
Q
As with the halogens, a more reactive metal will?
A
-Displace a less reactive metal.
7
Q
What is the equation for the Thermite reaction?
A
-Fe2O3+2Al=Al2O3+2Fe.
8
Q
Fe2O3+2Al=Al2O3+2Fe. In this reaction what is oxidized and what is reduced and what is the spectator ion?
A
- Oxide= spectator ion.
- Aluminium is oxidized.
- Iron is reduced.
9
Q
Define Ore?
A
-A natural deposit containing a mineral of an element to be extracted, that is financially viable. (you make money out of it)
10
Q
What are metals in Native form?
A
-These are metals in the ground that are not reacted with rocks around them. they are normally very nonreactive.
11
Q
Examples of metals found in native form?
A
-Gold, Silver, Copper.
12
Q
Examples of metals found as minerals?
A
-Potassium, sodium, lithium.
13
Q
Why is Sodium able to displace Cu from copper chloride?
A
-This is because a more reactive metal can be displace a less reactive metal from its compounds.
14
Q
What is the blast furnace used for?
A
-Used to extract iron from iron ore.
15
Q
Iron ore is called?
A
-Haematite Fe2O3.
16
Q
What three raw materials are used?
A
-Haematite, limestone, coke (carbon).
17
Q
What is Coke?
A
-Coke is a form of Carbon that is burned to produce heat.
18
Q
The CO2 will react with more coke..?
A
-To form carbon monoxide CO.
19
Q
What is carbon monoxide?
A
-A reducing agent.
20
Q
What do reducing agents do?
A
-They reduce other substances as the reducing agent is oxidized.
21
Q
What is the equation for CO2+C
A
-CO2+C=2CO
22
Q
What do you do when the blast furnace has got up to temperature?
A
-Haematite Fe2O3 is added. This will reduce the carbon monoxide.
23
Q
Equation for when Haemitie is added to blast furnace?
A
-Fe2O3 + 3CO = 2Fe + 3CO2
24
Q
What is limestone and what is is used for?
A
-As a rock silicone dioxide acid limestone calcium carbonate is added to neutralize it. Firstly the calcium carbonate thermally decomposes to form calcium oxide
25
How is Slag formed?
-Calcium oxide neutralizes the silicone dioxide to form calcium silicate (slag)
26
What is the purpose of carbon in a blast furnace?
-Carbon reacts with the oxygen to form CO2 and heat, then reacts with more coke to form CO, which is then a reducing agent.
27
Why is limestone added?
-Is added to neutralize it. firstly the calcium carbonate thermally decomposes to form calcium oxide.
28
What is electrolysis?
-When they are melted or in solution ionic compounds can be separated by passing an electric current through the liquid.
29
What is metal attracted to in electrolysis?
-Metals have a positive charge, so are attracted to the negative cathode. Metal ions are Cations.
30
What is non-metals attracted to in electrolysis?
-Non-metals have a negative charge, so are attracted to the positive anode. Non-metal ions are an-ions.
31
Which metals in the reactivity series do we usually extract from their ores by electrolysis?
-These are all the metals that we can not extract using carbon. By being displaced, such as aluminium.
32
What is aluminium ore called?
-Bauxite.
33
What is the melting point of Bauxite?
-2050oC.
34
When extracting aluminium form its ore what is oxidised and what is reduced? 2Al2O3 = 4Al + 3O2
-Aluminium is reduced and oxygen is oxidized.
35
What are the anodes made of?
-Graphite.
36
What does Cryolite do?
-Adding cryolite to the bauxite will lower its operating temperature to 700oC.
37
Where will aluminium form?
-At the Cathode.
38
Where will oxygen be attracted to?
-The anode, where it will react to form carbon dioxide. This is why anodes need replacing over time.
39
Why do the anodes need replacing over time?
-This is because the oxygen will react with the graphite to produce CO2 intern wearing away the anode.
40
Why is graphite used as a anode?
-Because it has a high melting temperature, and is a conductor.
41
How is aluminium taken out?
-The aluminium sinks to the bottom and is then run of at intervals.
42
Ways of protecting metals?
-Painting, oiling, coat in plastic, coating in less reactive metals.
43
What happens in sacrificially protection?
-The more reactive metal will react with the oxygen instead of the less reactive metal, even if the surface is scratched, so the more reactive metal has been sacrificed.
44
What are the four most reactive metals in the reactivate series?
-Potassium- Sodium- Lithium- Calcium.
45
What are the four least reactive metals in the reactivate series?
-Platinum- Gold- silver- copper. This is because they are so nonreactive they are also found in natural form always. they don't react in the soil.
46
Explain why the cryolite and aluminium oxide mixture must be kept molten for electrolysis?
-This is so that the aluminium can be separated and be attracted to the negatively charged cathode lining. Also to allow movement of ions to the appropriate electrode. this can not be done in a solid form.
47
Why is a mixture of aluminium oxide and cryolite used, rather than aluminium oxide alone?
-Cryolite is used as a solvent to dissolve the Al2O3, to make the liquid electrolyte. Also therefore the melting point of the Al2O3 is reduced.
48
Write a half equation to show the reaction at the positive electrode?
-2O- = O2 + 2e-.
49
Write a half equation to show the reaction at the negative electrode?
-Al3+ +3e- = Al.
50
Explain why the extraction of aluminium in this way is reduction?
-Al3+ ions gain electrons to become aluminium metal. gain of electrons is reduction.
51
Explain why the carbon anodes need to replaced at regular intervals?
-Oxygen is produced at the carbon anodes. Oxygen reacts with carbon to form carbon dioxide, this process is therefore slowly wearing down the down the anodes so that they will eventually need to be replaced. C + O2 =CO2.
52
Why is aluminium such a useful metal?
-This is because it is resistant to corrosion, so it is good for buildings and aircraft etc. It is also very lite. This is because aluminium has a layer of aluminium oxide at its surface.
53
Where are aluminium smelters normally found?
-Possibly by the coast because of cooling and hydro electric power. It is also where bauxite can be mined and also transportation can take place easily.
54
What is a displacement reaction?
-If a reactive element comes into contact with the compound of a less reactive element a chemical reaction may take place. The less reactive element is removed from the compound and replaced by the more reactive element.
55
Examples of displacement reactions, chlorine + sodium bromide =
-Most reactive is chlorine, therefore chlorine + sodium bromide = sodium chloride + bromide
56
Examples of displacement reactions, chlorine + sodium iodide =
-Most reactive is chlorine, therefore, chlorine + sodium iodide = sodium chloride + iodine.
57
What 3 raw materials does a blast furnace use?
-Hematite, limestone and coke (carbon).
58
Why is Haematite added?
-When the blast furnace has got up to temperature heamitite (Fe2o3) is added, this is reduced by the carbon monoxide.
59
Describe how reactions with water and dilute acids can be used to deduce the following order of re activity: K,Na,Li, Ca,Mg, Zn, Fe and Cu?
-You can see that K, Na, Li react very violently with water, therefore we can infer that these are the most reactive, the rest react with various acids. Use the reactivity series to see what is more reactive then what.
60
Explain how the methods of extraction of iron and aluminium are related to their positions in the reactivity series?
-This is because of the fact that iron can only be displaced from there oxides by carbon.
61
What is a oxidizing agent?
-Something that will oxidize something else.
62
Why do we have to replace the positive carbon made electrode after a while?
-This is because the carbon reacts with oxygen to form carbon dioxide.
63
What is iron used for?
-Pure iron is soft and easily shaped because its atoms are arranged in a regular way that lets layers of atoms slide over each other. Pure iron is too soft for many uses.
64
What conditions does Iron rust?
-Iron and steel rust when they come into contact with water and oxygen. Both water and oxygen are needed for rusting to occur. In the experiment below, the nail does not rust when air or water is not present. Remember that 21 per cent of the air is oxygen.
65
How can the rusting of iron be prevented in terms of using materials?
-It can be coated in a material such as paint etc.
66
How is sacrificial protection used?
-A peace of an element is used and is normally coated by the metal, this element will be more reactive then the main element there for the surrounding atmosphere will react with the most reactive element.
67
What are Redox reactions?
Redox reactions, or oxidation-reduction reactions, primarily involve the transfer of electrons between two chemical species. The compound that loses an electron is said to be oxidized, the one that gains an electron is said to be reduced.
68
Displacement reaction with Zinc and copper sulphate.
Zu + CuSO4 -> ZuSO4 + Cu, Cu is displaced.
69
Explain how Zinc blocks prevent ships from rusting? (2)
- Zinc is more reactive than iron or steel.
| - Zinc reacts with water instead of steel or iron. Prevents iron from losing electrons.
70
How do you know if (aq)?
solid + liquid =solution(aq) Solution is dissolved in a liquid. This is always (aq) unless they say a solid has been formed.
71
What is the Thermite reaction?
The reaction where Aluminium displaces iron because it is more reactive to form Aluminium oxide and Iron, that can then be used.
72
Uses of thermite reaction?
Extract Iron.
| Join railway tracks.
73
Equation for rust with iron and water?
water + iron + oxygen -> hydrated iron (III) oxide
74
How can distillation be used to extract compounds from elements?
This can be due to the heating point difference.
75
Blue Color Precipitate?
Copper (II)
76
How can Copper be purified?
Electrolysis.
77
When purifying copper what is used as the positive electrode (anode)
Impure copper.
78
When purifying copper what is used as the negative electrode (cathode)
pure copper.
79
anode is the?
positive electrode.
80
cathode is the?
negative electrode.
81
One use of copper and why?
Electric cabling.
| Ductile.
82
How does limestone remove silicon dioxide? (4)
Limestone decomposes.
Forms Calcium oxide.
neutralizes silicon dioxide which then forms Slag or Calcium Silicate.
83
Method of separation for ethanol from a mixture of ethanol and water?
fractional distillation
84
Method of separation for water from copper(II) sulfate solution?
Simple distillation
