Silver Nitrate in Ethanol Test for aliphatic halides

Standards, as done in the Classification Tests for Halides lab

1-chlorobutane 1-bromobutane 1-iodobutane
2-chlorobutane 2-bromobutane 2-iodobutane
2-chloro-2-methylpropane 2-bromo-2-methylpropane
benzyl chloride bromobenzene

Procedure

Place approximately 0.25 mL of each compound into a test tube. Add 2 mL of a 1% ethanolic silver nitrate solution to the material in each test tube, noting the time of addition. After the addition, shake the test tube well to ensure adequate mixing of the compound and the solution. Record the time required for any precipitates to form. If no precipitates are seen after 5 minutes, heat the solution on the steam bath for approximately 5 minutes. Note whether a precipitate forms in the test tube. Continue slow reactions for up to 45 minutes at room temperature.

Positive Test

alkyl halide - Production of solid silver halide salt is a positive test.

acyl halide - Production of solid silver carboxylate salt is a positive test. This solid should redissolve in dilute nitric acid.

carboxylic acid - Production of solid silver carboxylate salt is a positive test. This solid should redissolve in dilute nitric acid.

sulfonyl chloride - Production of solid silver sulfonate salt is a positive test. This solid should redissolve in dilute nitric acid.

Complications

1.The time and temperature required to form the solid salt can vary widely.
2.Carboxylic acids have been known to react in this test, giving false positives.