What are piezo-electric crystals ?

What are piezoelectric crystals ? Give their important uses.

What is piezoelectric crystal?

What are point defects in crystals ? Describe the Schottky defects in crystals.

What do you mean by defect in a crystal? What are point defects in a crystal?

What are isomorphous crystals? Give examples.

What are the causes of electrical conductivity of a semiconductor?

What is an electric screen ?

What is an electric circuit?

What is an electric charge ?

What is Schottky defect? Is it a stoichiometric or non-stoichiometric defect? What type of ionic crystals are likely to show this type of defect? Does the presence of this defect in a crystal increase or decrease the density of the crystal? Explain.