Chemical Bonds

2. Biological, chemical, and physical properties of matter result from the ability of atoms to form bonds based on electrostatic forces between electrons and protons, and between atoms and molecules.

a. atoms combine to form molecules by sharing electrons to form covalent or metallic bonds, or by exchanging electrons to form ionic bonds.
b. chemical bonds between atoms in molecules such as H2, CH4, NH3, H2CCH2, N2, Cl2, and many large biological molecules are covalent.
c. salt crystals such as NaCl are repeating patterns of positive and negative ions held together by electrostatic attraction.
d. in a liquid the inter-molecular forces are weaker than in a solid, so that the molecules can move in a random pattern relative to one-another.
e. how to draw Lewis dot structures.
f.* how to predict the shape of simple molecules and their polarity from Lewis dot structures.
g.* how electronegativity and ionization energy relate to bond formation.
h.* how to identify solids and liquids held together by Van der Waals forces or hydrogen bonding, and relate these forces to volatility and boiling/melting point temperatures.