PRS Questions: Acid-Base reactions

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PRS Questions Acid-Base reactions

• CH3CO2H(aq) NaOH(aq) ?
• 1. CH3CO2H2(aq) NaO(aq)
• 2. CH3CO2-(aq) H2O(l) Na(aq)
• 3. CH4(g) CO2(g) H2O(l)

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PRS Questions Acid-Base reactions

• HCN(aq) NH3(aq) ?
• 1. NH4(aq) CN-(aq)
• 2. H2CN(aq) NH2-(aq)
• 3. C2N2(s) 3 H2(g)

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Precipitation Reactions

• Solubility of Ionic Compounds

dissolving
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To Determine Solubility 1. identify the two
ions 2. soluble ions with no exceptions
never form precipitates 3. use
listing under soluble/insoluble, but
check to see if its an exception
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Examples

• Soluble or Insoluble?
• NaNO3
• FeCl3
• Fe(OH)3
• BaSO4
• AgNO3
• AgCl

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More Examples

• Soluble or Insoluble?
• K3PO4
• Fe3(PO4)2
• PbCl2
• FeSO4
• (NH4)2S
• PbS

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PRS Example 1

• Which of the following is soluble?
• AlPO4
• PbBr2
• Al(OH)3
• FeSO4

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PRS Example 2

• Which of the following is insoluble?
• Al(NO3)3
• PbC2O4
• NaOH
• FeF3

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Precipitation ReactionsNet Ionic Equations

• Pb(NO3)2 K2CrO4 ? ?
• Pb(NO3)2 KI ? ?

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Precipitation ReactionsNet Ionic Equations

• Pb(NO3)2 K2CrO4 ? ?
• Pb(NO3)2 KI ? ?
• BaCl2 KNO3 ?

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Return to Acid-Base ReactionsFind the hidden
bases

• Thing to know Anions of weak acids are bases.
• Example CH3COOH weak acid
• CH3COO- therefore weak base
• HCN weak acid
• CN- weak base
• H3PO4 weak acid
• PO43- weak base

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Return to Acid-Base ReactionsFind the hidden
bases

• HCl NaCN ? ?
• HCl AlPO4 ? ?
• HCl CaC2O4 ? ?

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Gas Forming Reactions

• 2 H CO32- ? CO2(g) H2O(l)
• 2 H SO32- ? SO2(g) H2O(l)
• 2 H M ? H2(g) M2(aq)
• M metal, like Mg or Fe