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 à 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