laboratory preparation of h2s

It is prepared in the laboratory by the action of iodine on ethyl alcohol or acetone, in the presence of alkali. This is called haloform reactio..

In laboratory, magnesium sulphate is prepared by dissolving magnesium, its oxide, hydroxide or carbonate in dilute sulphuric acid and evaporating the resulting solution, when colorless efflorescent crystals of the heptahydrate, MgSO 4 .7H 2 O, crystallize ou..

Calcium carbonate is prepared in the laboratory by passing carbon dioxide gas into lime water. The resulting precipitate is filtered, washed and dried. The product obtained is known as precipitated chalk. Excess of carbon dioxide should be avoided since this leads to the fo..

Air, free from moisture and carbon dioxide, is bubbled through boiling mercury. The oxygen of the air combines with the mercury to form mercuric oxide, which is a red solid (Fig.13.1)...

Laboratory Preparation of Alkenes - In the laboratory, alkenes are usually prepared from either alcohols or haloalkanes (alkyl halide..

Laboratory Preparation of Alkynes - There are only a few methods available for the preparation of alkynes, in contrast to alkanes and alkenes. These are given bel..

Hydrogen is prepared in the laboratory by treating granulated zinc with dilute sulphuric acid or dilute hydrochloric acid in col..

In the laboratory, alkenes are usually prepared from either alcohols or haloalkanes (alkyl halides..

Ethyne is prepared by the action of water on calcium carbide. The gas thus produced is collected by the downward displacement of wat..

In laboratory, dinitrogen is prepared by heating an aqueous solution containing equivalent amounts of ammonium chloride and sodium nitrite. ..