Electrolysis 
Q1.
This question is about electrolysis.
(a)     Metal spoons can be coated with silver.
This is called electroplating.
Suggest one reason why spoons are electroplated.
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(1)
(b)     When sodium chloride solution is electrolysed the products are hydrogen and chlorine.
(i)      What is made from chlorine?
 
Tick () one box.	
Bleach		
Fertiliser		
Soap		
(1)
(ii)     Sodium chloride solution contains two types of positive ions, hydrogen ions (H+) and sodium ions (Na+).
Why is hydrogen produced at the negative electrode and not sodium?
 
Tick () one box.	
Hydrogen is a gas.		
Hydrogen is less reactive than sodium.		
Hydrogen ions move faster than sodium ions.		
(1)
(iii)    Hydrogen and chlorine can be used to produce hydrogen chloride.
The diagrams in Figure 1 show how the outer electrons are arranged in an atom of hydrogen and an atom of chlorine.
 
Complete Figure 2 to show how the outer electrons are arranged in a molecule of hydrogen chloride (HCl).
 
(1)
(iv)    What is the type of bond in a molecule of hydrogen chloride?
 
Tick () one box.	
Covalent		
Ionic		
Metallic		
(1)
(v)    Why is hydrogen chloride a gas at room temperature (20 °C)?
 
Tick () two boxes.	
Hydrogen chloride has a low boiling point.		
Hydrogen chloride has a high melting point.		
Hydrogen chloride is made of simple molecules.		
Hydrogen chloride does not conduct electricity.		
Hydrogen chloride has a giant structure.		
(2)
(c)     Aluminium is produced by electrolysis of a molten mixture of aluminium oxide and cryolite.
This is shown in Figure 3.
 
(i)      Name a gas produced at the positive electrode.
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(1)
(ii)     Aluminium ions move to the negative electrode.
Explain why.
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(2)
(iii)    At the negative electrode, the aluminium ions gain electrons to produce aluminium.
What is this type of reaction called?
 
Tick () one box.	
Combustion		
Oxidation		
Reduction		
(1)
(iv)    Aluminium has layers of atoms, as shown in Figure 4.
 
Complete the sentence.
Metals can be bent and shaped because the layers of atoms can _________
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(1)
(d)     Electrodes used in the production of aluminium are made from graphite.
(i)      Which diagram, A, B or C, shows the structure of graphite?

The structure of graphite is shown in diagram		
(1)
(ii)     The temperature for the electrolysis is 950 °C.
Use the correct answer from the box to complete the sentence.
 
cross links        a giant ionic lattice        strong covalent bonds	
The graphite does not melt at 950 °C because
graphite has _____________________________ .
(1)
(Total 14 marks)