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InterviewSolution
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which of the following minerals is known asn orpiemnt?A. `As_(2)S_(3)`B. `As_(4)S_(4)`C. `HgS`D. `PbS` |
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Answer» Correct Answer - 1 Many minerals are sulphide ores. The most common of these are listed in given table. `|{:("Formula","Common name","Systematic name."),(HgS,"Cinnabar","Mercury" (II) "sulphide"),(Pbs,"Galena","Lead" (II) "sulphide"),(FeS_(2),"Pyrite","Iron" (II) "sulphide"),(ZnS,"Sphalerite","Zinc sulphide"),(As_(2)S_(3),"Orpiment","Diarsenic trisulphide"),(Sb_(2)S_(3),"Stibnite","Diantimony trisulphide"),(CuFeS_(2),"Chalcopyrite","Copper" (II) "iron" (II) "sulphide"):}|` Orpiment a yellow mineral ,is natural arsenic trisulphide `(As_(2)S_(3))` while realgar a red mineral ,is natural tetrarsenic tetrasulphide `(As_(4)S_(4))` Sulphides tend to be used for specialized purposes.The intense black antimony trisulphide `(Sb_(2)S_(3))` was one of the first cosmetic,being used as eye shadow from earliest recorded times Today sodium sulphide is the sulphide in highest demand between `10^(5)` and `10^(6)` tonnes is produced every year by the high temperatuer reduction of sodium sulphate with coke: `Na_(2)SO_(4)(s)+2C(s)rarrNa_(2)S(l)+2CO_(2)(g)` Sodium sulphide is used to remove hair form hides in the tanning of leather it is also used in ore separation by floation for the manufacture of sulphur containing dyes ,and in the chemical industry, such as the precipitaiton of toxic metal ions ,particularly lead. Other sulphides in commercial used are selenium disulphide `(SeS_(2))` a common additive to antisandruff hair sampoos and moluybdenum `(IV)` sulphide `(MoS_(2))`, an excellent lubricant for metal surfaces ,either on its own or suspended in oil. Metal sulphides tend to be dense, opaque solids , and it is this property that makes the bright yellow cadumium sulphide `(CdS)` a popular pigment for oil painitng. |
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