Question

Type metal is an alloy of lead, antimony and tin. It consists of:
A.Equal amounts of the three metals
B.More amount of lead
C.More amount of antimony
D.More amount of tin

Answer 1

Hint: To answer this question, you must be familiar with type metal and its characteristics. The type metal is required to be cheap, plentifully available, hard and wear resistant. These characteristics can help us understand the various elements used to make type metal.

Complete step by step answer:
Type metal is used in printing used for the mechanical line casting and individual characters typesetting. It is an alloy of lead, antimony and tin. Lead is a soft metal and is thus easy to work with. It can be cast easily as it melts at a relatively lower temperature than many metals. It is exceptionally malleable and ductile but has very little tensile strength. As a result, it is used for making type metal. However, lead shrinks while it solidifies and thus the letters made from casting lead are not sharp enough to be used for printing. Also, the letters made with pure lead would tend to deform soon during use.
The other constituent of type metal is tin. Since it is harder, stiffer and tougher than lead, tin makes the type metal tough and gives it resistance to wear. It also promotes the fluidity of the alloy in molten state.
Antimony is a brittle and fusible crystalline metalloid. The addition of antimony to the alloy provides the much needed improvements in the alloy’s properties like hardness and wear resistance. It has a significant impact on the sharpness of the type alloy as it reduces the shrinkage during the solidification of the alloy.
From the characteristics, it is clear that lead must be added in more amount forming the majority of the type metal, while antimony and tin are added in lesser amounts comparatively.

Thus, the correct answer is B.

Note:
The composition of the type metal is around 80 percent lead, 15 percent antimony and 5 percent tin. By varying the proportions of the metals, the desired properties can be produced for different kinds of typecasting and printing.