okay and i don't understand what they are asking for for chemical characteristics.

i was thinking like density, melting point, and boiling point but arent those physical too?

Yes, those are physical properties, also. Chemical properties are those that involve a reaction. For example, a chemical property (I've forgotten the question and the element but let's pick oxygen) for oxygen might be

2H2 + O2 ==> 2H2O or
4Fe + 3O2 ==> 2Fe2O3