Answer:
A pure substance has a definite chemical composition
Silver and lead are special elements, where silver is insoluble in all halogen anions (like AgCl, AgI, AgBr)
and lead is insoluble in sulphates and halogen anions ( PbSO4, PbCl2, etc.)
Mercury is special because it is the only metal that is a liquid at room temperature
hope this helps!!
The last photo because its molecular formula is C3H4.
Answer:
Sulfur is a non mental, because it is consistent with the 3 physical properties listed for nonmetals