Qualitative identification of volatile oils.

appearance:
(1) take a variety of volatile oils (pine, mint, clove, chen and cinnamon oil) to observe its color, whether there is a special aroma, and spicy burning taste.
(2) Volatility: take
filter paper
a small piece of crumbs, drop a drop of mint oil, place for 2 hours or micro-heat after observing the filter paper for clear traces of oil (in contrast to vegetable oil).(3) pH test: (free acid or phenol).take a sample with 5 drops of ethanol to pre-wet the extensive pH
test paper
with distilled water for inspection, such as acidicity, showing free acid or phenolic
compound
, the remaining sample ethanol liquid for the following (7) (8) test.(4) FeCl3 reaction (phenol detection):
take a drop of the sample, dissolved in 1 ml of ethanol, add 1% FeCL3 alcohol liquid 1 to 2 drops, such as blue purple or green, indicating phenolic.(5) benzene test (ketone, aldehyde)
take 2,4-dinitrobenzene test liquid 0.5 to 1 ml, plus 1 drop of sample of aldehyde-free alcohol solution, strong vibration, if there is ketone compounds, should be precipitated yellow and orange red precipitation, if no reaction, can be placed 15min after observation.(6) Fluorescent test:
drops sample ethanol liquid on the filter paper, sprays the wine with 0.05% fluorescent water solution, and then exposes the sheet to 5% Br2/Col4 steam in wet, with double-bonded terpenes (e.g. volatile oil) yellow;(7) Scented aldehyde - Thick Sulphuric Acid Test:
Take a drop of volatile oil ethanol liquid on the filter paper, drop a new preparation of 0.5% balsamic aldehyde of thick acetic acid, yellow, brown, red or blue reaction..