# Precipitate Practice Problems ```Precipitate Practice Problems:
Complete and balance the following reactions, determining, in each case, if a precipitate
is formed.
KCl(aq) + Pb(NO3)2(aq)
AgNO3(aq) + MgBr2(aq)
Ca(OH)2(aq) + FeCl3(aq)
NaOH(aq) + HCl(aq)
NaCl(aq) + Hg2(NO3)2(aq)
Ca(OH)2(aq) + Na2CO3(aq)
Na2S(aq) + FeCl3(aq)
Write the formula, complete ionic, and net ionic forms for each of the following
equations:
Aqueous nickel (II) chloride reacts with aqueous sodium hydroxide to give a nickel(II)
hydroxide precipitate and aqueous sodium chloride.
Solid potassium metal reacts with water to give aqueous potassium hydroxide and hydrogen
gas.
Aqueous sodium hydroxide reacts with aqueous phosphoric acid to give water and aqueous
sodium phosphate.
Aqueous sodium sulfide reacts with aqueous copper (II) nitrate.
Aqueous hydrogen fluoride reacts with aqueous potassium hydroxide to give water and
aqueous potassium fluoride.
Stoichiometry of Precipitation Reactions:
1. Calculate the mass of Ag2S produced when 125mL of 0.200M AgNO3 is added to excess
Na2S solution.
2. What mass of Fe(OH)3 is produced when 35mL of a 0.25M Fe(NO3)3 solution is mixed
with 55mL of a 0.180M KOH solution?
3. Calculate the mass of CaSO4 produced when 10mL of 6.0M H2SO4 is added to 100mL of
0.52M Ca(NO3)2.
4. You are given the equation: 2AgBr(s) + 1Na2S2O3(aq)
1Ag2S2O3(aq) + 2NaBr(aq).
What mass of AgBr can be dissolved by 750.mL of 0.300M Na2S2O3?
5. Given the following chemical equation, determine the theoretical yield of B2H6 if exactly
100.0g of LiAlH4 was allowed to react with 225g of BF3.
3LiAlH4 + 4BF3
3LiF + 3AlF3 + 2B2H6
Answers: 1. 3.10g Ag2S
2. 0.35g Fe(OH)3
3. 7g CaSO4
4. 84.5g AgBr
5. 45.9g B2H6
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