Butane (C₄H₁₀) is produced in industry by the THERMAL cracking of long-chain hydrocarbon molecules, as shown in the equation below - NSC Physical Sciences - Question 4 - 2016 - Paper 2
Question 4
Butane (C₄H₁₀) is produced in industry by the THERMAL cracking of long-chain hydrocarbon molecules, as shown in the equation below. X represents an organic compound ... show full transcript
Worked Solution & Example Answer:Butane (C₄H₁₀) is produced in industry by the THERMAL cracking of long-chain hydrocarbon molecules, as shown in the equation below - NSC Physical Sciences - Question 4 - 2016 - Paper 2
Step 1
4.1.1 ONE condition required for THERMAL cracking to take place.
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Answer
One required condition for thermal cracking to take place is high temperature or high pressure. This allows for the breaking of molecular bonds in long-chain hydrocarbons.
Step 2
4.1.2 The molecular formula of compound X.
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The molecular formula of compound X is C₈H₁₈, which is octane.
Step 3
4.1.3 The homologous series to which compound X belongs.
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Compound X belongs to the alkane homologous series, which includes saturated hydrocarbons with the general formula CₙH₂ₙ₊₂.
Step 4
4.2 Explain which ONE of the gases (X or BUTANE) decolourises the bromine water.
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Compound X decolourises the bromine water since it is an alkene and contains a double bond, allowing it to react with bromine. In contrast, butane is a saturated alkane lacking double bonds and does not react in this way.
Step 5
4.3.1 IUPAC name of compound P.
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The IUPAC name of compound P is 2-chlorobutane.
Step 6
4.3.2 Type of reaction labelled I.
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The type of reaction labelled I is chlorination.
Step 7
4.3.3 Structural formula of compound Q.
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The structural formula of compound Q is as follows:
CH₃
|
H₃C-C-CH
|
OH
In this case, Q represents an alcohol derived from butane through substitution.
Step 8
4.3.4 The type of addition reaction represented by reaction III.
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The type of addition reaction represented by reaction III is hydration, as it involves the incorporation of a water molecule into the alkene to form an alcohol.
