Pearson Edexcel International GCSE (9–1) · CHEMISTRY · Section
Physical properties
19 practice questions
Practice questions
11–19 of 19
Question 11
3 marks · Normal
Answer and see the solution →An alkene molecule contains 14 hydrogen atoms. Calculate the number of carbon atoms it contains. Show your working.
Question 12
3 marks · Normal
Answer and see the solution →Hexene (C6H12) and butene (C4H8) are both alkenes. Explain why hexene has a higher boiling point than butene, referring to their structure and trends among alkenes (C2–C4).
Question 13
4 marks · Normal
Answer and see the solution →The table below shows the number of carbon atoms and the molecular formula for three alkenes. For each, state if the formula is correct for an alkene. If not, explain your answer.
Alkene Number of C atoms Molecular formula W 4 C4H8 X 5 C5H12 Y 3 C3H6 Question 14
1 mark · Normal
Answer and check →Which statement about the physical properties of alkenes with 2 to 4 carbon atoms is correct?
- A.They are all gases at room temperature.
- B.They are all liquids at room temperature.
- C.Their boiling points decrease as the number of carbon atoms increases.
- D.They are solids at room temperature.
Question 15
2 marks · Normal
Answer and see the solution →State the general formula for alkenes and give the displayed formula for propene.
Question 16
4 marks · Normal
Answer and see the solution →The table below gives information about three alkenes.
Alkene Number of carbon atoms Boiling point (°C) Ethene 2 -104 Propene 3 -47 Butene 4 -6 (a)[2 marks]Describe the trend in boiling points shown in the table.
(b)[2 marks]Explain why the boiling point increases as the number of carbon atoms increases.
Question 17
2 marks · Hard
Answer and see the solution →A student claims that all alkenes have the same general formula. State this general formula and explain how it shows that alkenes are unsaturated.
Question 18
5 marks · Hard
Answer and see the solution →The physical properties of alkenes with 2 to 4 carbon atoms show a trend.
(a)[2 marks]State the physical state of ethene, propene and butene at room temperature.
(b)[2 marks]Describe how the boiling points of these alkenes change as the number of carbon atoms increases from ethene to butene.
(c)[1 mark]Explain why the trend you described in part (b) occurs.
Question 19
2 marks · Hard
Answer and see the solution →State the general formula for alkenes. Explain, using your formula, how you can determine the number of hydrogen atoms in an alkene containing 9 carbon atoms.