Answer
a) chemical
b) physical
c) physical
d) chemical
e) chemical
f) chemical
Work Step by Step
a) Since the property involves a chemical reaction (combustion) a chemical reaction must occur and thus, it must be a chemical property
b) The composition of steel can be measured using methods other than a chemical reaction and the property is not related to a chemical reaction.
c) Density can be measured based on the mass and volume and thus does not require a chemical reaction for the property to be measured and it is not related to the reactivity of the compound.
d) The process of a compound dissolving is a chemical reaction and thus the solubility of a compound in a particular solvent can only be determined via a chemical reaction.
e) Combustion is a chemical reaction and thus, whether a substance combusts in air can only be determined through a chemical reaction.
f) The process of ripening is a chemical reaction and can only be determined through a chemical reaction.
