Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Unit
Principles of Chemistry
991 practice questions
Topics covered
- States of Matter102 practice questions
- Elements, Compounds and Mixtures69 practice questions
- Atomic Structure108 practice questions
- The Periodic Table103 practice questions
- Chemical Formulae, Equations and Calculations Part 119 practice questions
- Chemical Formulae, Equations and Calculations Part 2144 practice questions
- Ionic Bonding143 practice questions
- Covalent Bonding68 practice questions
- Metallic Bonding19 practice questions
- Electrolysis198 practice questions
Practice questions
731–740 of 991
Question 731
3 marks · Easy
Answer and see the solution →Bonding and Atomic Arrangement Carbon Allotrope Number of covalent bonds per carbon atom Type of structure Diamond Graphite C60 fullerene Complete the table by filling in the number of covalent bonds per carbon atom and the type of structure for each allotrope.
Question 732
1 mark · Easy
Answer and see the solution →State why graphite is soft.
Question 733
3 marks · Easy
Answer and see the solution →(a)[1 mark]State the electrical conductivity for each of the following carbon structures: diamond, graphite, and C60 fullerene.
(b)[1 mark]Explain why diamond does not conduct electricity.
(c)[1 mark]Explain why graphite conducts electricity.
Question 734
2 marks · Easy
Answer and see the solution →C60 fullerene contains 60 carbon atoms. If each carbon atom forms 3 bonds, calculate the total number of covalent bonds in one C60 molecule.
Question 735
2 marks · Normal
Answer and see the solution →Describe the structure and bonding in graphite.
Question 736
4 marks · Normal
Answer and see the solution →The table shows some physical properties of diamond and graphite.
Physical properties of diamond and graphite Substance Melting point/°C Hardness Conducts electricity Diamond 3550 Very hard No Graphite 3600 Soft Yes (a)[2 marks]Explain, in terms of their structures and bonding, why diamond is much harder than graphite.
(b)[2 marks]Explain, in terms of bonding, why graphite conducts electricity but diamond does not.
Question 737
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 738
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 739
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 740
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.