Photo AI
Butene reacts with steam to produce butanol - Edexcel - GCSE Chemistry - Question 5 - 2016 - Paper 1
Question 5
Butene reacts with steam to produce butanol. C₄H₈ + H₂O → C₄H₉OH (i) Calculate the maximum mass of butanol, C₄H₉OH, that can be produced when 1.4 kg of butene, C₄H... show full transcript
Worked Solution & Example Answer:Butene reacts with steam to produce butanol - Edexcel - GCSE Chemistry - Question 5 - 2016 - Paper 1
Step 1
Calculate the maximum mass of butanol, C₄H₉OH, that can be produced when 1.4 kg of butene, C₄H₈, reacts with excess steam.
Answer
-
First, we need to calculate the moles of butene:
moles of butene = \frac{mass}{molar \ mass} = \frac{1.4 \ kg}{0.056 \ kg/mol} = 25.0 \
The reaction shows that one mole of butene produces one mole of butanol. Therefore, 25 moles of butene will produce 25 moles of butanol.
-
Now, calculate the mass of butanol produced:
mass = moles \times molar \ mass = 25 \ moles \times 0.074 \ kg/mol = 1.85 \ kg
Thus, the maximum mass of butanol that can be produced is 1.85 kg.
Step 2
What type of reaction takes place between butene and steam?
Answer
The reaction between butene and steam is a B dehydration reaction. This is because the addition of steam to the alkene results in the formation of an alcohol, which is characteristic of a hydration reaction involving alkenes.
Step 3
Using the results, comment on the structures of the hydrocarbons X, Y and Z.
Answer
Based on the results of the bromine water test:
- Hydrocarbon X and Y both react with bromine water to become colourless, indicating that they are unsaturated hydrocarbons (alkenes) capable of undergoing electrophilic addition reactions with bromine.
- Hydrocarbon Z, on the other hand, does not cause the bromine water to change colour and therefore is likely a saturated hydrocarbon (alkane) which does not react with bromine under these conditions.