Some chemical reactions of organic compounds
4 marks · NormalThe table below shows four reactions of organic compounds.
| Equation | Reaction |
|---|---|
| 1. CH4 + Cl2 → CH3Cl + HCl | |
| 2. C2H4 + H2 → C2H6 | |
| 3. 2C3H7OH + 9O2 → 6CO2 + 8H2O | |
| 4. C2H4 + Br2 → C2H4Br2 |
For each equation, classify the reaction as substitution, addition, or combustion.
State how you used the equations to identify at least two of the reaction types.
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
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(a (1)) substitution
(a (2)) addition
(a (3)) combustion
(a (4)) addition
(b) For example, in equation 2, two reactants combine to form one product, so it is addition. In equation 1, a chlorine atom replaces a hydrogen atom, so it is substitution. · must show Identification of clues in the equation, e.g., counting reactants/products, seeing groups replaced.
Common mistakes: Not matching reactants to products; missing the definition of reaction types.
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Marking points
a1 (a) · 1 mark · Correctly classifies reaction 1 as substitution
a2 (a) · 1 mark · Correctly classifies reaction 2 as addition
a3 (a) · 1 mark · Correctly classifies reaction 3 as combustion
b (b) · 1 mark · Explains, using evidence from equations, how at least one type was identified
Worked solution
a) 1. substitution 2. addition 3. combustion 4. addition
b) In equation 2, two reactants make one product, so that's addition. In equation 1, a Cl atom replaces H, so that's substitution.