Question: why sncl2 is solid and sncl4 is liquid?
Answer: The cation with smaller ionic radius approves the fajan's rule more than other cation. So,SnCl4 has more covalent characters than SnCl2. And we know the melting and boiling point of ionic compounds are higher than covalent compounds. So in normal temperature SnCl2 is solid and SnCl4 is liquid.