Question

The percentage of carbon in cast iron is
A: $5 - 10$
B: $0.25 - 2.5$
C: $2.5 - 4.5$
D: $0.12 - 0.2$

Answer 1

Hint: Cast iron is a group of iron carbon alloys with carbon content more than $2\% $ . An alloy is a combination of metals or metals combined with one or more other elements.

Complete step by step answer:
Cast iron is an alloy of iron that contain $2\% - 4\% $ carbon, along with varying amounts of manganese, silicon and traces of impurities such as sulphur and phosphorus so answer to this question is option C that is $2.5 - 4.5$

Additional information: There are two major types of iron produced wrought iron and cast iron.
Wrought iron: it is virtually pure elemental iron that is heated in a furnace before being worked with hammers on an anvil. Hammering iron expels most of the slag from the material and weld the iron particles together. It has high tensile strength due to which it is used in making beams in large construction projects such as bridges and high rise buildings it is also used for making decorative pieces.
Cast iron: it is produced by smelting carbon alloys having carbon content more than $2\% $ after smelting metal is poured into a mold. The primary difference in production between wrought iron and cast iron is that cast iron is not worked with a hammer and tools. Various types of cast iron are produced using different heat treatments and processing techniques types of cast iron are Grey iron, White iron, Malleable iron, ductile iron and graphite iron
Gray iron is characterized by the flake shape of the graphite molecules in the metal.
White iron when sheared, the fractured face appears white due to absence of graphite.
White iron can be further processed into malleable iron through a process of heat treatment.
Ductile iron is also called nodular iron. It obtains its special properties through addition of magnesium into the alloy.
Graphite iron has a graphite structure and associated properties that are a blend of gray and white iron.

Note: Do not get confused with the carbon percentage of other iron carbon alloys. Cast iron has properties like hardness and abrasive resistance which is due to the presence of carbon content in it. Carbon presence gives all the properties to the iron.