Question

Spelter is impure of.
A) Zinc.
B) Silver.
C) Copper.
D) Iron.

Answer 1

We know that spelter is a zinc-lead alloy. It is softer and has a lower melting point. The name can also refer to a copper-zinc alloy used for brazing, or to pure zinc. Metals are a substance which has high electrical and thermal conductivity due to the presence of free electrons.

Complete step by step answer:
Let us discuss the extraction of Zinc from its ore,
Zinc Mining:
The most commonly available ore utilized in the extraction of Zinc is named blende also referred to as Zinc Sulfide. The extraction of zinc is harder than the extraction of other metals because, at temperatures where metals like iron typically begin to melt, zinc may be a gas. Zinc has a low boiling point, at such temperatures; zinc will escape with exhaust gases. Zinc sulfide doesn't contain a high percentage of zinc and hence it must be concentrated.
Now we see the concentration of Zinc ore:
The simplest concentration method for zinc ore is froth flotation.
We must know about the Froth Flotation process is particularly used to remove impurities from sulfide ores. The ore is powdered and a suspension is made in water. The most ingredients of the froth flotation are the Collectors and Froth Stabilizers. Collectors such as pine oils, fatty acids, etc. increase the wet ability of the metal a part of the ore and allow it to make froth and Froth Stabilizers such as cresols, aniline, etc. sustain the froth. The oil wets the metal and therefore the water wets the impurities. Paddles and air constantly fire up the suspension to make the froth. This frothy metal is skimmed off the highest and dried to recover the metal.
Metal from concentrated ore:
The next step within the extraction of zinc is named Roasting. The concentrated ore is finely ground into small pieces then suspended during a rising stream of air. The sulfur content is often reduced hugely with this process. This also converts the blend to $ZnO$ which is much more reactive. The reaction is,
$2ZnS + 3{O_2} - > 2ZnO + 2S{O_2}$
Zinc Oxide is then mixed with Coke and ground into fine pieces and heated at $1673{\text{ }}K$ in fire clay containers during a process which is additionally referred to as the Belgian Process. Here the zinc gets reduced to metallic Zinc. The carbon from coke acts because of the reducer during this reaction. The reaction is,
$2ZnO + C - > 2Zn + C{O_2}$
Spelter is impure of zinc which is in the form of slabs thrown from the liquid obtained in the process of reducing the ores. The most general commercial form of zinc metal is spelter.

So, the correct answer is Option A .

Note:
Since, the boiling point of Zinc is much back at, the zinc formed immediately vaporizes and distills over leaving non-volatile impurities like Cadmium, Lead, and Iron. This crude metal is named spelter. It is often further purified by fractionation.