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9 Ethanol, C₂H₅OH, burns in oxygen - OCR Gateway - GCSE Chemistry - Question 9 - 2020 - Paper 1
Question 9
9 Ethanol, C₂H₅OH, burns in oxygen. Carbon dioxide and water are made. Which equation for this reaction is correctly balanced? A C₂H₅OH + O₂ → CO₂ + H₂O B C₂H₅OH ... show full transcript
Worked Solution & Example Answer:9 Ethanol, C₂H₅OH, burns in oxygen - OCR Gateway - GCSE Chemistry - Question 9 - 2020 - Paper 1
Step 1
Which equation for this reaction is correctly balanced?
Answer
To determine the correctly balanced equation for the combustion of ethanol, we first need to write down the unbalanced equation:
In the balanced reaction, ethanol will react with oxygen to produce carbon dioxide and water. The process involves counting the number of atoms of each element on both sides of the equation and ensuring that they are equal.
Starting with option B:
In this equation, we have:
- Carbon: 2 (from C₂H₅OH) = 2 (from 2CO₂)
- Hydrogen: 6 (from C₂H₅OH) = 6 (from 3H₂O)
- Oxygen: 4 (from O₂) + 1 (from C₂H₅OH) = 7 = 4 (from 2CO₂) + 3 (from 3H₂O)
This shows that option B is balanced:
Thus, the answer is: B.