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Match the following compounds with the correct chemical test used to identify them: List I: P = Ethanol (CH3CH2OH), Q = Benzaldehyde (C6H5CHO), R = Phenol (C6H5OH), S = Acetic acid (CH3COOH) List II: 1 = Tollens test, 2 = Fehling solution test, 3 = Iodoform test, 4 = Bromine water test, 5 = NaHCO3 test

1. P->3; Q->2; R->5; S->4
2. P->3; Q->1; R->4; S->5
3. P->2; Q->2; R->3; S->4
4. P->4; Q->3; R->4; S->5

Correct answer: P->3; Q->1; R->4; S->5

Solution

P (Ethanol): CH3CH2OH has the CH3CH(OH) unit, giving a positive iodoform test (yellow CHI3 precipitate). Test 3. Q (Benzaldehyde): an aldehyde, gives positive Tollens test (silver mirror). Does NOT reduce Fehling solution (aromatic aldehydes don't). Test 1. R (Phenol): decolorizes Br2 water immediately (electrophilic aromatic substitution). Test 4. S (Acetic acid): reacts with NaHCO3 to give CO2 bubbles (strong enough acid). Test 5. Answer: P->3, Q->1, R->4, S->5.

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