Periodic Table Reactions Flashcards
NaCl with water
pH 7
Dissolves readily
NaCl (s) —> Na+ (aq) + Cl- (aq)
MgCl2 with water
pH 6.5
Dissolves with slight hydrolysis to give slightly acidic solution
Equation forms Mg(H2O)5OH+ complex
AlCl3 with water
pH 3
Dissolves with appreciable hydrolysis to give an acidic solution
Forms aluminium complex
SiCl4 with water
pH 2
Dissolves in water due to complete hydrolysis to form acidic solution
Forms SiO2 (s) and 4HCl (aq)
PCl5 with water (excess)
pH 2
Dissolves in water due to complete hydrolysis to form acidic solution
Forms phosphoric acid and HCl (aq)
PCl5 with water (limited)
pH 2 Gives POCl3 (l) and 2HCl (g)
PCl5 with added water (after limited)
Starting from POCl3 (l)
Gives phosphoric acid and HCl (aq)
Sodium oxide with water
pH 13
Reacts vigorously to form strongly basic solution
Magnesium oxide with water
pH 9
Reacts less vigorously to form weakly alkaline solution
Due to more exothermic lattice energy, it is more difficult to break ionic lattice structure, so MgO is sparingly soluble
Aluminium oxide with water
No reaction (insoluble in water) Very exothermic lattice energy
Silicon dioxide with water
No reaction (insoluble in water) Strong and extensive covalent bonds between Si and O atoms in lattice structure
Phosphorus oxide with water
pH 2
Reacts readily with water to form acidic solution
Gives phosphoric acid
Sulfur trioxide with water
pH 2
Reacts readily with water to form acidic solution
Gives sulphuric acid
Sodium oxide/hydroxide with acids
Undergo neutralisation, forms salt solution
Magnesium oxide/hydroxide with acids
Undergo neutralisation, forms salt solution
Aluminium trioxide with acids
Undergo neutralisation to form salt solution
Al2O3 (s) + 6HCl (aq) —> 2AlCl3 (aq) + 3H2O
Aluminium trioxide with bases
Undergo neutralisation to form salt solution
Al2O3 (s) +2NaOH (aq) +3H2O (l) –> 2NaAl(OH)4 (aq)
Silicon dioxide with bases
Only reacts with hot concentrated NaOH Forms Na2SiO3 (aq) and water
Phosphorus oxide with bases
Forms Na3PO4 and water
Sulfur trioxide with bases
Forms Na2SO4 and water
What is the reason behind diagonal relationships?
The elements have similar charge density and electronegativity. They then have similar polarising powers, making it such that they have similar chemical properties.
Li and Mg are both thermally stable, Be and Al are both amphoteric (their oxides have covalent character, so they have acidic character)
