1.
State what is meant by a hydrocarbon. [1]
JD SCIENCE
Organic chemistry and fuels
Answer all questions. Show working. Answers are in a separate file on the Worksheets page — do not look at them until you have finished.
2.
State what is meant by an alkane. [1]
3.
State what is meant by an alkene. [1]
4.
State what is meant by fractional distillation. [1]
5.
State what is meant by cracking. [1]
6.
State what is meant by complete combustion. [1]
7.
State what is meant by incomplete combustion. [1]
8.
State what is meant by a polymer. [1]
9.
State what is meant by a functional group. [1]
10.
State what is meant by an ester. [1]
11.
Owain is asked about a hydrocarbon in a WJEC Chemistry paper.
(a) Describe a hydrocarbon. [2]
(b) Explain why a hydrocarbon is important in this topic. [3]
12.
Owain is asked about an alkane in a WJEC Chemistry paper.
(a) Describe an alkane. [2]
(b) Explain why an alkane is important in this topic. [3]
13.
Owain is asked about an alkene in a WJEC Chemistry paper.
(a) Describe an alkene. [2]
(b) Explain why an alkene is important in this topic. [3]
14.
Owain is asked about fractional distillation in a WJEC Chemistry paper.
(a) Describe fractional distillation. [2]
(b) Explain why fractional distillation is important in this topic. [3]
15.
Owain is asked about cracking in a WJEC Chemistry paper.
(a) Describe cracking. [2]
(b) Explain why cracking is important in this topic. [3]
16.
Owain is asked about complete combustion in a WJEC Chemistry paper.
(a) Describe complete combustion. [2]
(b) Explain why complete combustion is important in this topic. [3]
17.
Write the formula of the alkane with 9 carbons. [3]
18.
Balance C₃H₈ + O₂ → CO₂ + H₂O [3]
19.
Mr of C₂H₄ (C=12, H=1) [3]
20.
A 100 cm³ sample of alkene decolourises bromine water. What does this show? [3]
21.
Percentage of C in CH₄ [3]
22.
Moles of CO₂ from 2 mol C₂H₆ complete combustion (2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O) [3]
23.
Owain carries out a WJEC-style required practical linked to organic chemistry and fuels. This is a typical WJEC required-practical style question.
(a) Identify the independent variable and the dependent variable. [2]
(b) State one control variable and explain why it must be controlled. [2]
(c) Suggest one improvement or source of error and how it affects the result. [2]
24.
Owain carries out collecting valid data for organic chemistry and fuels. This is a typical WJEC required-practical style question.
(a) Identify the independent variable and the dependent variable. [2]
(b) State one control variable and explain why it must be controlled. [2]
(c) Suggest one improvement or source of error and how it affects the result. [2]
25.
Owain carries out drawing a graph for organic chemistry and fuels. This is a typical WJEC required-practical style question.
(a) Identify the independent variable and the dependent variable. [2]
(b) State one control variable and explain why it must be controlled. [2]
(c) Suggest one improvement or source of error and how it affects the result. [2]
26.
Owain carries out evaluating a method about organic chemistry and fuels. This is a typical WJEC required-practical style question.
(a) Identify the independent variable and the dependent variable. [2]
(b) State one control variable and explain why it must be controlled. [2]
(c) Suggest one improvement or source of error and how it affects the result. [2]
27.
Compare a hydrocarbon with an alkane. [4]
28.
Compare an alkane with an alkene. [4]
29.
Compare an alkene with fractional distillation. [4]
30.
Compare fractional distillation with cracking. [4]
31.
Apply your knowledge of incomplete combustion to this situation: yellow flame [3]
32.
Apply your knowledge of a polymer to this situation: addition polymers from alkenes [3]