Question: why sncl4 is covalent and sncl2 is ionic?
Answer: As SnCl4 show Sn 4+ oxidation state and tends to have higher positive charge and its size is smaller than Sn 2+ i.e Sn4 + polarise Cl- more than the Sn2+ ion i.e SnCl4 is covalent in nature. Hence SnCl2 is ionic whereas SnCl4 is covalent.