The table shows information about two alkenes - Edexcel - GCSE Chemistry - Question 4 - 2013 - Paper 1
Question 4
The table shows information about two alkenes.
Complete the table to show the names and structures of these alkenes.
(a) ethene
(b) (i) Ethene is an unsaturated co... show full transcript
Worked Solution & Example Answer:The table shows information about two alkenes - Edexcel - GCSE Chemistry - Question 4 - 2013 - Paper 1
Step 1
Complete the table to show the names and structures of these alkenes.
96%
114 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The structure of ethene (C₂H₄) is represented as:
H H
\ /
C=C
/ \
H H
So the answer is:
Name: Ethene
Structure: C₂H₄
Step 2
State what is meant by unsaturated.
99%
104 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
An unsaturated compound is one that contains a double bond between carbon atoms. This means that it has the ability to add more atoms or groups to its structure, typically through chemical reactions.
Step 3
Describe what is seen when ethene is passed into bromine water.
96%
101 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
When ethene is passed into bromine water, a color change occurs. The brown color of bromine water turns colorless as the bromine reacts with ethene, indicating that a reaction has taken place.
Step 4
Explain what is meant by cracking.
98%
120 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
Cracking is a process used in the petrochemical industry to break down long-chain hydrocarbons into smaller molecules. This involves either thermal or catalytic methods to decompose larger hydrocarbons into alkenes and other useful products.
Step 5
Complete the sentence by putting a cross ✗ in the box next to your answer.
97%
117 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The reaction taking place when molecules of ethene react to form poly(ethene) is D: polymerisation.
Step 6
Explain why the presence of waste plastic in landfill sites causes problems.
97%
121 rated
Only available for registered users.
Sign up now to view full answer, or log in if you already have an account!
Answer
The presence of waste plastic in landfill sites causes significant environmental problems because plastics are not biodegradable. They can persist in the environment for hundreds of years, leading to soil and water contamination and posing threats to wildlife. Additionally, the accumulation of plastic waste can contribute to the increase of landfill sizes and the depletion of available land resources.
