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Questions
Give a simple chemical test to distinguish between the following pair of compounds:
Ethanal and Propanal
Give a chemical test to distinguish between propanal and ethanal.
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Solution
| Ethanal | Propanal |
| Ethanal gives a yellow precipitate on heating with iodine in the presence of sodium hydroxide (positive Iodoform test). | Propanal will not give any reaction on heating with iodine in the presence of sodium hydroxide (negative Iodoform test). |
Ethanal gives the iodoform test, but propanal does not.
\[\ce{CH3CHO + \underset{Hypoiodite}{\underset{Sodium}{3NaOI}} ->[NaOH/I2][Heat] HCOONa + \underset{yellow ppt}{CHI3\downarrow} + 2NaOH}\]
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||
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