State reasons- (i) the shining surface of some metals becomes dull when exposed to air. (ii)metal sulphides occur mainly in rocks but metal halides occur mostly in sea and lake waters.
Answers
Answered by
83
i) When some metals get exposed to air there is an oxidation process occurring on the outer layer of the metal. Due to the oxidation; a new layer covers the existing metal; hiding its original view; giving it a dull appearance. Almost all metals combine with oxygen to form metal oxides.
Metal + Oxygen → Metal oxide
(ii) Metal halides are soluble in water and therefore get dissolve in rain water and are carried to lakes and sea during weathering of rocks. On the other hand metal sulphides being insoluble in water remain in the rocks.
Metal + Oxygen → Metal oxide
(ii) Metal halides are soluble in water and therefore get dissolve in rain water and are carried to lakes and sea during weathering of rocks. On the other hand metal sulphides being insoluble in water remain in the rocks.
Similar questions