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This question is about compounds of carbon - OCR Gateway - GCSE Chemistry - Question 22 - 2020 - Paper 1
Question 22
This question is about compounds of carbon. Look at the displayed formulae of ethane, propane and ethene. (a) Ethane and propane are both members of the homologous... show full transcript
Worked Solution & Example Answer:This question is about compounds of carbon - OCR Gateway - GCSE Chemistry - Question 22 - 2020 - Paper 1
Step 1
Ethane and propane are both members of the homologous series called the alkanes. Write down two reasons why ethane and propane are members of the same homologous series.
Answer
- Ethane and propane have the same general formula, which is CₙH₂ₙ₊₂, where 'n' represents the number of carbon atoms.
- Both of these compounds are saturated, meaning they have single (covalent) bonds between their carbon atoms.
Step 2
Why do ethene molecules undergo polymerisation but ethane molecules do not?
Answer
Ethene molecules undergo polymerisation because they contain a carbon-carbon double bond, which allows them to link together to form long chains. Ethane, on the other hand, only has single bonds and does not have the ability to form these polymer chains.
Step 3
Complete the diagram to show the displayed formula of poly(ethene).
Answer
The displayed formula of poly(ethene) consists of a chain of carbon atoms each bonded with single bonds. The structure can be illustrated as follows:
H H
| |
H-C-C-H
| |
H-C-C-H
| |
H H
|
n
In this representation, all carbon atoms are connected by single bonds, and each carbon atom has hydrogen atoms attached to it.