1.         Name the following covalent compounds.

a.      SiO2     silicon dioxide

b.     CS2          carbon disulfide

c.      NO      nitrogen monoxide

d.     PCl3     phosphorus trichloride

e.      PF5      phosphorus pentafluoride

2.         First figure out if the compound is covalent, regular ionic or an ionic compound with a transition metal.  Then name it appropriately.

a.     PCl5                 phosphorus pentachloride

b.     KBr                 potassium bromide

c. CuSO4 copper sulfate

d..      PI3                    phosphorus triodide

e.      K2CO3              potassium carbonate

f.      NH 4I                ammonium iodide

3.         Write formulas for the following:

a.     magnesium phosphate              Mg3(PO4)2

b.     lithium hydrogen carbonate     LiHCO3

c.     diphosphorus pentoxide           P2O5

d.     silicon tetrachloride                SiCl4

e.     calcium hydroxide                   Ca(OH)2

f.      sodium fluoride                       NaF

g.      nitrogen trifluoride                  NF3

4.         The scum-producing reaction between soap and Ca+2 can be represented by:

Ca+2   + NaC17H35CO2        Ca(C17H35CO2)2 + 2 Na+1

From the above formulas, determine the charge of the stearate(C17H35CO2) polyatomic ion.

Use any of the compounds containing C17H35CO2.

Let x = charge of C17H35CO2 ;

But calcium is +2, and the charges have to add up to zero, so:

            2x + 2 = 0

            x = -1