Pre-Lab Assignment 1.
Describe the following trends in properties of oxides across Period 3.
(a)
(b)
Their appearance.
Their volatility
Their structure.
Their acid-base character
Their conductivity
(d)

See explanation

Explanation:

From left to right, the oxides across period 3;

i) Period 3 oxides all appear white in colour. They are all crystalline solids and their melting points decrease from left to right.

ii) The volatility of period 3 oxides increases from left to right across the periodic table

iii) The metallic oxides on the right hand side adopt giant ionic structures. Silicon oxide which is in the middle of the period forms a giant covalent structure. Oxides of other elements towards the right hand side form molecular oxide structures.

iv) The acidity of oxides of period 3 increases from left to right. Metals on the left hand side form basic oxides while non-metals on the right hand side form acidic oxides. The oxide of aluminium in the middle is amphoteric.

v) The oxides of period 3 elements do not conduct electricity. However, the metallic oxides on the lefthand side conduct electricity in molten state. The non-metallic oxides on the right hand side are molecular hence they do not conduct electricity under any circumstance.

answer; talc and gypsum;