Question

Many pure metals like copper, iron and gold are very soft and as such are considered unsuitable for certain uses. Metallic objects around us such as cooking utensils, statues, ornaments, guns etc. are actually not made up of pure metals. Instead of pure metals, alloys are used in the design of most of the useful objects. Making alloys enhances the basic properties of a metal which is the primary constituent (metal) of an alloy.
How does electrical conductivity and melting point of a metal change when it is converted to its alloy by mixing a small amount of an element in it?

Hint:

Alloying generally reduces the electrical conductivity and the melting point of a metal. The change depends on the type and amount of the alloying element.

Answer 1

When a metal is converted into its alloy by mixing a small amount of another element, its electrical conductivity and melting point typically change in the following ways: 1. Electrical Conductivity: The electrical conductivity of a metal generally decreases when it forms an alloy. This is because the addition of another element disturbs the regular arrangement of atoms in the metal, making it harder for electrons to flow freely. - In pure metals, free electrons move easily, providing good electrical conductivity. However, in alloys, the foreign atoms act as obstacles to the flow of electrons, reducing conductivity. 2. Melting Point: The melting point of a metal is often lowered when it is converted into an alloy. The presence of a second element disrupts the uniformity of the metal’s crystal lattice, making it easier for the alloy to melt compared to the pure metal. For example, the addition of zinc to copper to form brass reduces the melting point and decreases electrical conductivity.