Solder is an alloy of: A. 70 % Pb, 30% Sn B. 33 % Pb, 67% Sn C. 80 % Pb, 20% Sn D. 90 % Cu, 10% Sn
Hint: Alloy is defined as the combination of two metals, or a metal with a non – metal, to form an alloy.
Complete step by step answer: A metallic solid or liquid that is composed of a homogeneous mixture of two or more metals and non – metals or metalloid elements, usually for the purpose of imparting or increasing specific characteristic or properties. Examples of alloys are steel, bronze and brass. In alloy, the atoms of the original metal are replaced with the atoms that have the same size from another material. Brass is an example of alloy of copper and zinc. On the other hand, mix atoms together that have different sizes. Atoms are added to the original metal that are much smaller in size. For example, steel is prepared by adding a small number of carbon atoms in between the large number of atoms in iron. A solder is a fusible metal alloy with a melting point or melting point range of $90 - 450^\circ C$, used in a process called soldering where it is melted to join metallic surfaces. It is especially useful in electronics and plumbing. Alloys that melt between $180^\circ $and $190^\circ C$ are the most commonly used alloys. Solder is an alloy of tin and lead. The alloy of tin and lead have characteristic weight percentages. Ideally, solder is $63$ percent tin and $37$ percent lead.
Therefore, the correct option is (B).
Note: We have to remember that alloys are metal solutions of different metals and other elements are melted together resulting in different properties.