Marcy creates a model that compares elements and compounds. Her model is shown. Which statement can Marcy support with her model?
An element is highly reactive, and a compound is stable.

An element can exist in any state, and a compound can only be liquid.

An element contains multiple substances, and a compound contains only one pure substance.

An element is made of a single type of atom, and a compound is made of two or more atom types.

1)each group 16 element has how many valence electrons? ( )4 ( )6 ( )8 ( )16 2)how many dots appear in the dot structure for calcium ion, ca2+? ( )zero ( )one ( )two ( )eight 3) which of the following atoms forms a cation to obtain an octet of outer shell electrons? ( )magnesium ( )oxygen ( )fluorine ( )helium 4) an al3+ ion contains 13 protons and 10 electrons. ( )true ( )false 5) valence and non-valence electrons are represented in lewis dot structures. ( )true ( )false

In a water molecule, hydrogen and oxygen are held together by a(an) bond. a) double covalent b) ionic c) nonpolar covalent d) hydrogen e) polar covalent

What is the percentage of hydrogen in nitrogen trihydride