Question

Name the sulphide ore of zinc.

Answer 1

Hint: Ores are sediments or rocks that occur in the Earth surface naturally and it contains valuable minerals. Metals are extracted from these ore which is termed as extractive metallurgy.

Complete step by step answer:
The sulphide ore of zinc is mineral sphalerite. Sphalerite has the chemical composition $\left( {{\rm{Zn,Fe}}} \right){\rm{S}}$and it is mostly found in the igneous rock, metamorphic rock and in the sedimentary rocks. In sphalerite, the content of iron is 25% in weight and it also contains traces of other compounds such as indium, cadmium, germanium etc. in small amounts. The sphalerite appears as a perfect cleavage that is responsible for the lustre property of the compound.

Additional information:
${\rm{ZnS}}$ has a molar mass of 97.474 g/mol and the solubility of this compound is negligible. This compound has a tetrahedral geometry and a standard enthalpy of formation value -204.6 kJ/mol. We know that ${\rm{ZnS}}$ exists in two crystalline forms. In both the form, the coordination geometry of the Zn and the S is tetrahedral. The stable cubic form of this compound is called as zinc blende or sphalerite. The hexagonal form of this compound is called the mineral wurtzite. The transition of the sphalerite form to the wurtzite form takes place at ${\rm{1020^\circ C}}$ approximately. The tetragonal form of this compound is called as polhemusite which has the chemical formula $\left( {{\rm{Zn,Hg}}} \right){\rm{S}}$.
${\rm{ZnS}}$also has various uses such as it is used as a luminescent material, in optical material is it used as optical infrared material, it is used as pigment, it is used as a catalyst and it is also has semiconductor properties.
We can prepare ${\rm{ZnS}}$ in the laboratory by the ignition of a mixture of sulfur and zinc. It can be given as,
${\rm{Z}}{{\rm{n}}^{2 + }} + {{\rm{S}}^{2 - }} \to {\rm{ZnS}}$

Note:
Metals are extracted from ore by a process known as extractive metallurgy. Some common methods of extracting metals from the ores are mining, refining, smelting, leaching etc.