(a) Name the charged particles which attract one another to form electrovalent compounds.

(b) In the formation of electrovalent compounds; electrons are transferred from one element to another. How are electrons involved in the formation of a covalent compound ?

(c) The electronic configuration of nitrogen is (2, 5). How many electrons in the outer shell of a nitrogen atom are not involved in the formation of a nitrogen molecule ?

(d) In the formation of magnesium chloride (by direct combination between magnesium and chlorine), name the substance that is oxidized and the substance that is reduced.

An element X has 2 electrons in its M shell, it forms bond with an element Y which has 7 electrons in its third orbit.

(a) Write the formula of the compound formed.

(b) Which nearest inert gas electronic configuration will element X and Y acquire?

(c) Show using an orbital diagram the formation of compound between X and Y.

In the formation of (i) Oxygen molecule (ii) Carbon tetrachloride molecule, state the following:

(a) Electronic configuration of nearest inert gas attained.

(b) How many electrons are shared/transferred in bond formation?

(c) Which type of bonds these compounds form?

(d) Draw the orbital diagrams?

A sample of an element A contains two isotopes ¹⁶₈A and ¹⁸₈A. If the average atomic mass of the element is 16.2 amu, calculate the percentage of the two isotopes in this sample.