Which best describes matter?

Achange in the number of neutrons in an atom will change an blank . when the number of protons changes in an atom, a new element will form.

Stage in which a star’s outer layers have started to cool and grow outward?

Ageochemist examines a piece of metal that he found in the soil. he performs tests to identify the metal from its density, electrical conductivity, and melting point. which statement best describes his investigation? a. he is determining physical properties that are sufficient to identify the metal. b. he is determining chemical properties that are sufficient to identify the metal. c. he is determining physical properties that are insufficient to identify the metal. d. he is determining chemical properties that are insufficient to identify the metal.