Preparation and Properties of Tin II Oxide

Preparation and Properties of Tin(II) Oxide. Add an aqueous solution of ammonia to 10 ml of a tin(II) chloride solution up to the complete precipitation of tin(II) hydroxide. Pour off the mother liquor, wash the precipitate by decantation, filter it off, and dry it in a drying cabinet at 70-80 °C. 

Place dry tin(II) hydroxide in a porcelain boat into a refractory tube connected to a Kipp gas generator charged with marble and hydrochloric acid. Displace the air from the apparatus with a stream of dry carbon dioxide, and by gradually heating the tube with the flame of a gas burner, roast the tin(II) hydroxide up to the complete removal of water vapour. 

When the substance is dehydrated, remove the boat and spill out the tin(II) oxide into a heated porcelain bowl. What do you observe What is the colour of tin(11) and tin(IV) oxides What oxidation state do the most stable tin compounds correspond to  

Preparation of a-Stannic Acid. Add a 10% ammonia solution to a tin(IV) chloride one up to complete precipitation. Wash the product with water by decantation until the chloride ions are removed and filter it off on a Buchner funnel. Test the reaction of a-stannic acid with water, acids, and alkalies. Do the properties of this acid remain the same after prolonged standing or boiling Perform the relevant experiments. 

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