Page 23 - Curriculum Visions Dynamic Book

Silver is part of specialised high- capacity silver–zinc and silver– cadmium batteries. It is used in mirrors in which the glass keeps the silver from tarnishing (the reflection comes from the back or silvered side of the mirror). Silver salts are part of light-sensitive photographic film.
Geology
Silver occurs in native form. It is widely distributed, but the total in the Earth’s crust is relatively small.
It occurs in ores that contain other precious metals.The most important ore is silver sulphide.
Biology
Silver does not occur in living things.
 Silver is used for many mirrors, either on the surface of a supporting material, or on the back of a sheet of glass to protect it from tarnishing.
 Silver deposited on the inside of a round- bottomed flask
 Dendritic silver. Native silver, which
is tarnishing grey on exposure to the air, set in a mineral groundmass.
 Silver metal reacts with hydrogen sulphide gas in the air to produce black silver sulphide.
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