Ch. 15 solution                        test                               30 points                                              chemistry

Show your work in an organized manner, include (i) any relevant equation (or formula), (ii) conversion factor(s), (iii) put the proper units in your calculations and answer, and (iv) have the proper number of significant figures in your answer. 

1. Solve; what is the __.  [10 points]

a.  % NaCl in an aqueous solution containing 3.0 g NaCl and 45 g water ?

b. molarity of glucose (C6H12O6) in an aqueous solution containing 3.0 g glucose in 75 mL solution ?

2.  In an acid – base titration experiment, where ___; what is the concentration of the acid.  [10 points]

a.  15 mL of a 75 mM KOH is needed to titrate / neutralize a 35 mL aqueous solution of the acid, HCl

b. 25 mL of a 125 mM NaOH is needed to titrate / neutralize a 75 mL aqueous solution of the acid, H3PO4

3. In regards to the reaction,

25 mL Na3PO4(aq)  +  excess Zn(NO3)2(aq) →  1.0 g Zn3(PO4)2(s)  +  NaNO3(aq)

 what was the concentration of Na3PO4 prior to the addition of Zn(NO3)2 ?  [10 points]