Ch-3 Metals and Non-metals (Questions) Page 49

Question 1:	(i) Write the electron-dot structures for sodium, oxygen and magnesium. (ii) Show the formation of Na2O and MgO by the transfer of electrons. (iii) What are the ions present in these compounds?
Answer :	(i) The representation of elements with valence electrons as dots around the elements is referred to as electron-dot structure for elements. (ii) (iii) The ions present in Na2O are Na+ and O2− ions and in MgO are Mg2+ and O2− ions.
Question 2:	Why do ionic compounds have high melting points?
Answer :	Ionic compounds have strong electrostatic forces of attraction between the ions. Therefore, it requires a lot of energy to overcome these forces. That is why ionic compounds have high melting points.