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PROOFS OF THE PROPERTIES OF COPPER.

SECT. II.

EXPERIMENTAL PROOFS

OF

THE PROPERTIES OF COPPER

Experiment I.

Copper dissolves readily in diluted nitric acid.

(Preparation of nitrate of copper .)

JLjET copper filings be dissolved in a sufficient quantity of nitricacid of a moderate strength; when no further effervescence en-sues boil the acid gently upon the copper, until a pellicle appears.Decant the solution and evaporate it slowly, and when a strongpellicle is formed suffer it to crystallize. The salt thus obtainedis of a fine blue colour.

Experiment II.

Action of liquid ammonia on copper.

A singular phenomenon which attends the action of liquidammonia on copper has long attracted the notice of chemists.

If a bottle, provided with a ground stopper, be filled quitefull of liquid ammonia, and some copper filings be introduced,