Question

Spiegeleisen is an alloy of:
A. Cu + Zn + Ni
B. Ni + Cr
C. Mn + Si + C
D. Fe + Cr + Ni

Answer 1

Hint: In order to solve this question one must know about alloy. An alloy is a mixture or compound made up of one or more metals. Example of an alloy is when gold is mixed with silver to form white gold. Spiegeleisen is mainly a ferromanganese alloy.

Complete step by step solution:
Spiegeleisen contains approximately 15% manganese along small quantities of nonmetals like carbon and silicon. Spiegeleisen is also called specular spiegel iron or pig iron. It is lustrous and crystalline in nature.
It is used in the manufacture of steel by the Bessemer process.
Hence, Spiegeleisen is the alloy of Mn, Si and C. So the correct option is (C).
Additional information:
Ferromanganese is also known as a ferroalloy. It has a very high content of manganese. It is prepared by heating a mixture of oxides \[Mn{O_2}\] and \[F{e_2}{O_3}\] along with carbon, in either an electrical arc furnace or a blast furnace. The oxides undergo carbothermal reduction in the furnaces and thus produce the ferromanganese and these are used as a deoxidizer for steel.
Manganese is used in many alloys, and it is the key component in the manufacturing of steel due to its ability to harden and strengthen the steel. Also it reduces the critical cooling rate during hardening which means that it increases the hardenability of steel.

Note: Don’t confuse ferromanganese with ferromagnetism. Ferromagnetism is the property by which certain metals are attracted towards the magnets or they form permanent magnets. Ferromanganese is the alloy having high content of manganese and it is prepared by using oxides of manganese and iron.