Chemistry form 4 Text Book Answer 3

Quick Review E, pg 75

1.  (a)  Magnesium.  It is located on the left of Period 3.

     (b)  When across Period 3,  all the elements exist as solid except chlorine and 

            argon which are gases.

2.  (a)  (i)  sodium oxide, aluminium oxide

            (ii)  aluminium oxide, silicon(IV) oxide, sulphur dioxide

(b)   Sodium oxide is a basic oxide. 

Aluminium oxide is an amphoteric oxide.

Silicon(IV) oxide and sulphur dioxides are acidic oxides.

3.  (a)  Period 2.  They have two shells occupied with electrons.

     (b)  F, C, Li

     (c)  The electronegativity increases from lithium to fluorine. 

This is due to the increasing nuclei attraction on the valence electrons and    

the decrease in atomic size.