a. Zinc metal can be shaped into many different forms by hammering.
Property: Physical (This is a physical property because it describes how a substance can change its shape through a physical process, without undergoing a chemical change.)
b. Silver tarnishes, forming black silver sulfide.
Property: Chemical (This is a chemical property because it describes a reaction that results in the formation of a new substance, silver sulfide, due to a chemical change.)
c. Sodium metal is soft enough to cut with a butter knife.
Property: Physical (This is a physical property because it describes a characteristic related to the material's physical state and behavior under mechanical stress.)
d. Gold melts at 1064°C.
Property: Physical (This is a physical property because it describes the temperature at which a substance changes from a solid to a liquid state, which is a physical change.)