a)NaCl, MgCl2 , AlCl3, SiCl4
b)i)Aluminium has more / 3 delocalised electrons per atom than sodium making it to have strong metallic bonds hence high melting point while sodium has only 1 delocalised electron per atom
ii)Chlorine molecule is smaller compared to that of sulphur; thus van der waals forces in chlorine molecule are weaker than in sulphur OWTTE
iii) Magnesium chloride has giant ionic structure while aluminium chloride has molecular structure. Ionic bonds in magnesium chloride are strong and require a lot of energy to break while the van der waals forces in aluminium chloride are weak and require little energy to break
c)Sodium chloride dissolves in water without being hydrolysed while aluminium chloride dissolves in water and is hydrolysed with the production of hydrogen ions (H+) which are responsible for the acidic properties
d)Across the period the effective nuclear charge increases due to increase in number of protons; this increases the force of attraction between the nucleus and electrons in the outermost energy level hence more energy required to remove them.
e)Add water to the mixture; magnesium chloride dissolves while iron (III) does not. Filter the mixture to obtain iron (III) oxide as the residue. Wash the residue with distilled water and dry it between two filter papers
Kavungya answered the question on November 1, 2019 at 08:29
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