Question

The percentage of carbon in cast iron varies from:
A. 0.5 to 1
B. 0.1 to 0.5
C. 1 to 1.7
D. 1.7 to 4.5

Answer 1

Hint – The cast iron usually contains around 4 % of carbon, it is very hard and brittle.

Complete answer:
We have been asked about the percentage of carbon in cast iron.
So, first we should discuss cast iron.
Cast iron is a group of iron – carbon alloys with a carbon content more than around 2%.
It has relatively low melting temperature which makes it useful. It is made by reducing iron ore in a blast furnace. The liquid iron is cast and hardened. It never cracks or dent like a solid surface or stainless-steel sink because it has a high durability and strength, they can stand the test of time without succumbing easily to problems.
Cast irons are also naturally non-stick. So, it can be easily cleaned and things won’t stick to it.
Cast iron tends to be brittle and hard. The alloy constituents affect its colour when fractured.
Most cast irons have a chemical composition of 2.5 – 4.0% carbon, 1 – 3% silicon and the remaining are iron.
So, out of the given options, the best possible range is 1.7 to 4.5.

Hence, the correct option is D.

Note – whenever such types of questions appear, then always first know about the cast iron. About its composition, properties and then about the range in which carbon is there in it. As mentioned in the solution, the percentage of carbon in cast iron varies from 1.7 to 4.5.