The definition of a Lewis acid and base is: Acid is any substance that can accept a pair of nonbonding electrons, while that a Base is a species that contains a nonbonding pair of electrons, and in the reaction in the question:
SO3 + H2O -> H2SO3 + 2 OH-
We have SO3 as the conjugate base of the acid H2SO3 and H2O is acting as an acid in this occasion, therefore the answer is Acid
Mixing food coloring with water is a physical change.
<u><em>In metallic bonding, the valence electrons are free to move throughout the metal structure. Metallic bonding is the electrostatic attraction between the metal atoms or ions and the delocalized electrons. This is why atoms or layers are allowed to slide past each other, resulting in the characteristic properties of malleability and ductility.</em></u>
