Distinguish on the basis of heating in dry test table.
(i) Zinc carbonate and copper carbonate
(ii) Zinc nitrate and copper nitrate
Answers
Differences on dry heating of given compounds is written below-
(i) Zinc carbonate and copper carbonate
Zinc carbonate on thermal decomposition yields products named, zinc oxide and carbon dioxide.
Zinc oxide is yellow in color, when hot.
The precipitate turns white on cooling.
Carbon dioxide can be detected by formation of white precipitate in lime water.
Copper carbonate on dry heating yields two products namely, copper oxide and carbon dioxide.
Copper carbonate is green in color, which turns black on formation of copper oxide.
Carbon dioxide again can be tested with the same method, as stated above.
(ii) Zinc nitrate and copper nitrate
Zinc nitrate on dry heating gives product namely, zinc oxide, nitrogen dioxide and oxygen.
Nitrogen dioxide is marked with red fumes.
Oxygen can be checked with burning splinter test.
Precipitate of zinc oxide formed is yellow in color, when hot.
On cooling it turns white.
Copper nitrate on heating gives products namely, copper oxide, nitrogen dioxide and water.
Copper nitrate is blue in color, which turns into black color of copper oxide.
Reddish brown fumes mark presence of nitrogen dioxide.