An organic liquid, when reacted with concentrated sulfuric acid, produces a compound that decolourises bromine water - HSC - SSCE Chemistry - Question 11 - 2010 - Paper 1

To determine the formula of the organic liquid that reacts with concentrated sulfuric acid and produces a compound that decolourises bromine water, we need to consider the properties of the compounds given in the options.

1. Understanding the Reaction: The organic liquid should be one that can react to form an unsaturated compound, which is capable of decolourising bromine water. This indicates the presence of a double bond or a reactive functional group.

2. Analyzing the Options:

   • (A) C₆H₁₂: This is a saturated hydrocarbon (alkane) and will not decolourise bromine water.
   • (B) C₆H₁₄: This is also a saturated hydrocarbon and will not decolourise bromine water.
   • (C) C₆H₁₁OH: This is an alcohol, and depending on its structure, it may react to remove water and form alkenes, which can decolourise bromine water.
   • (D) C₅H₁₁COOH: This is a carboxylic acid and can also decolourise bromine water, but alcohols are typically more reactive in this context.

3. Conclusion: Considering all the above, the organic liquid that fits the criteria of the question is C₆H₁₁OH, which is an alcohol capable of forming an alkene that decolourises bromine water.