Substances X, Y, and Z need to be identified. Substance X can be broken down by a physical change. Substance Y cannot be broken down by a chemical or physical change. Substance Z can only be broken down by a chemical change. What can be concluded about these substances?

Astable electron arrangement for an atom is one that does not easily change. how is this arrangement arrived at? a. valence electrons are transferred or shared to create a full outer shell of electrons. b. valence electrons are discarded into space to create a full outer shell of electrons. c. protons (positive charge) pair with valence electrons (negative charge) to create a strong bond. d. outer shells with valence electrons are transferred or shared.