When impurities are added to an elastic substance, its elasticity

State the meaning of an elastic substance.

The process of adding impurities to a crystalline substance so as to change its properties like conductivity etc. is called…..

Which of the following substance have least elasticity ?

Which one of the following substances is not elastic ?

Which of the following substances has the highest elasticity

When is a body called elastic and when is it called plastic? Explain elastic limit.