Download 17-2: Precipitates - Trimble County Schools

17-2: Precipitates
Ion product (Q)
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Can be compared with Ksp to determine if an
aqueous soln of ions is supersaturated and
will form a precipitate
Ksp< Q, soln is supersat., will ppt
Ksp > Q, soln is unsat, will accept more ions
Ksp = Q, soln is saturated
Precipitation rxn
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A rxn in which 2 solns are mixed and a ppt
forms
Use solubility rules on page 574 to predict if a
ppt will form, and it so, what it is
All are double replacement reactions
Driving Forces of Rxns
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Driving forces allow less energy and are more
stable
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formation of a ppt
formation of a gas
formation of water
Complete ionic equation
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shows all soluble ionic substances as ions
Ex:
Net ionic equation
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Includes only those ions that undergo a
change
Ex:
Spectator ions
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ions that do not take part in a rxn
appear both before and after a reaction