In the cyanide process, silver is oxidized to a soluble complex and then reduced back to metal using zinc.
Ag
Silver (\(\text{Ag}\)) is extracted by the cyanide process (MacArthur-Forrest process), which involves oxidation and subsequent reduction. The reactions are:
\[4\text{Ag} + 8\text{CN}^- + \text{O}_2 + 2\text{H}_2\text{O} \rightarrow 4[\text{Ag}(\text{CN})_2]^- + 4\text{OH}^- \quad \text{(oxidation)},\]
\[2[\text{Ag}(\text{CN})_2]^- + \text{Zn} \rightarrow 2\text{Ag} + [\text{Zn}(\text{CN})_4]^{2-} \quad \text{(reduction)}.\]
Here:
\(\text{Ag}\) is oxidized to form a soluble complex \([\text{Ag}(\text{CN})_2]^-\).
\(\text{Ag}\) is then reduced by zinc to obtain pure metallic silver.
A block of mass 1 kg is pushed up a surface inclined to horizontal at an angle of \( 60^\circ \) by a force of 10 N parallel to the inclined surface. When the block is pushed up by 10 m along the inclined surface, the work done against frictional force is:
[Given: \( g = 10 \) m/s\( ^2 \), \( \mu_s = 0.1 \)]
A gas can be taken from A to B via two different processes ACB and ADB. When path ACB is used, \( 60 J \) of heat flows into the system and \( 30 J \) of work is done by the system. If path ADB is used, the work done by the system is \( 10 J \). The heat flow into the system in path ADB is:
The existence of metals often plays an important role in our survival, even if we are unaware of them. Our reliance on metals has been strong since the old industrial era. From buildings to jewelry, we utilize them for everything. But where do we acquire these metals from and how are they made? Let's read the occurrence of metal in more detail.
Metals are found in the earth's crust, and it seems to be a good place to extract them through various processes such as metallurgy. The process of extracting metals from ores is called metallurgy. Mining is the most common method of extracting metals from the earth.
In nature, metals are mostly found in mixed conditions. However, they can also be found in a free state. In its natural state, a native metal is one that can be found in its pure form or as part of an alloy. Most metals are exposed to natural processes such as oxidation and corrosion. As a result, only non-reactive metals such as gold, silver, platinum, and others are discovered in their native or open-free condition. Most metals are obtained as compounds, which must be filtered to remove contaminants before being employed in numerous applications.