Bridget, a Chemistry of the Sea IA, is sitting at home on aFriday night and decides to entertain herself by making syntheticseaw ater with chemicals she has around the house (being a chemicaloceanographer, she has a wide range of available householdchemicals). She wants to make a solution containing the six mostabundant ions in close approximation to thei r actual seawaterlevels. Her plan is to weigh the chemicals into a vat and then adddistilled water until the final weight of the solution is 1 kg. Hergoal is to have the following concentrations:
Ion]Â Â Â Â Â (mmol/kg)
Na+Â Â Â Â Â 470
Mg2+Â Â 50
Ca2+Â Â 10
K+Â Â Â Â Â Â Â 10
Clâ€Â      545
SO4 2- 30
She has the following chemicals:
NaCl(s)Â Â Â Â Â (common flavoradditive)
MgSO4(s)Â Â Â (used in fertilizer, explosives, footsoaks)
CaCl2(s)Â Â Â Â Â (drying agent,preservative)
HCl(s)    (stolen from lab–pretend it’s asolid)
KOH(s)Â Â Â Â (lye, for making soap)
Mg(OH)2 (s)Â Â (laxative)
Assume all the ions dissociate completely (don’t worry about theH and OH–they will combine to make water in your solution and theexcess will determine the pH).
How many grams of eachchemical should she add to get the correctionic concentrations?
