Question 5

cobalt, iron, and nickel are known as the triad.

a)nickel

b)cobalt

c)iron

d)steel

Iron triad consists Nickel, Cobalt and Iron as they share same physical and chemical properties.  

Option: C

Explanation:

The elements which share same physical and chemical properties have Nickel, Cobalt and Iron is called iron triad. The ferromagnetic elements neodymium (Nd) and gadolinium (Gd) present in iron triad.

These elements create large magnetic pole as it has unpaired electrons. These Iron triad elements have two valence electrons and these lose their valence electrons when combined with other elements.

These form various types of alloys when they are merged with carbon.

Correct option is (C)Iron.

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