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a and c are compounds. substance d is an element.
b and d are compounds. a and c are elements.
b is a compound, a, c and d are all elements
a and c are elements. substance d is a compound.

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.

Nuclear decay is the spontaneous decay of one element into a. an x-ray b. a ray of light c. another element

The term gas is limited to those substances that exist in the gaseous state at