Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Giant covalent structures
19 practice questions
Practice questions
11–19 of 19
Question 11
3 marks · Normal
Answer and see the solution →A student connects graphite, diamond and C60 fullerene electrodes into identical electric circuits. The student measures the current in each case:
Electrical current measured Substance Current/mA Diamond 0.0 Graphite 15.0 C60 fullerene 0.0 Question 12
3 marks · Normal
Answer and see the solution →C60 fullerene, diamond and graphite are all allotropes of carbon. Explain how the structure and bonding in C60 fullerene differs from that in diamond and graphite.
Question 13
4 marks · Normal
Answer and see the solution →The table shows the melting points and hardness for three forms of carbon.
Properties of carbon allotropes Allotrope Melting point/°C Hardness Diamond 3550 Very hard Graphite 3600 Soft C60 fullerene 280 Soft (a)[2 marks]Using only the data, identify which allotrope(s) have a giant covalent structure. Explain your reasoning.
(b)[2 marks]Using the data and your knowledge, explain why C60 fullerene has a lower melting point than graphite.
Question 14
1 mark · Normal
Answer and check →Which statement correctly compares the electrical conductivity of diamond, graphite, and C60 fullerene?
- A.Only graphite conducts electricity because it has delocalised electrons.
- B.Only diamond conducts electricity because it has a giant covalent structure.
- C.Diamond and C60 fullerene both conduct electricity, but graphite does not.
- D.All three conduct electricity equally well.
Question 15
2 marks · Normal
Answer and see the solution →Describe the bonding in diamond in terms of the arrangement of carbon atoms and the bonds formed.
Question 16
4 marks · Normal
Answer and see the solution →Diamond is a non-conductor of electricity and is very hard, while graphite is soft but conducts electricity.
(a)[2 marks]Explain, in terms of bonding and structure, why diamond does not conduct electricity.
(b)[2 marks]Explain, using bonding and the arrangement of atoms, why graphite is soft.
Question 17
2 marks · Hard
Answer and see the solution →Diamond is used for industrial cutting tools, while graphite is used as a lubricant. Explain, in terms of structure and bonding, why graphite can be used as a lubricant but diamond cannot.
Question 18
5 marks · Hard
Answer and see the solution →The three allotropes of carbon—diamond, graphite, and C60 fullerene—have different abilities to conduct electricity.
(a)[1 mark]State which, if any, of these allotropes can conduct electricity.
(b)[4 marks]For each allotrope, explain your answer by referring to their bonding and the movement of electrons.
Question 19
2 marks · Hard
Answer and see the solution →Describe the structure and bonding in C60 fullerene, referring to how carbon atoms are arranged and bonded in this allotrope.