InterviewSolution
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InterviewSolution
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`100mL` of a clear saturated solution of `Ag_(2)SO_(4)` is added to `250mL` of a clear saturated solution of `PbCrO_(4)` .will any precipitate form and if so what ?Given `K_(sp)` values of `Ag_(2)SO_(4),Ag_(2)CrO_(4),PbCrO_(4)& PbSO_(4)` are `1.4xx10^(-5),2.4xx10^(-12),2.8xx10^(-13)` and `1.6xx10^(-8)` respectively. |
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Answer» For `Ag_(2)SO_(4)hArr underset(2s)2Ag^(+)+underset(s)SO_(4)^(2-)` `K_(sp)=4s^(3)or s=3sqrt((K_(sp))/(4))=sqrt((1.4xx10^(-5))/(4))=1.52xx10^(-2)M` for `PbCrO_(4)hArr Pb^(2+)+CrO_(4)^(2-)` `K_(sp)=s_(1)^(2) or s_(1)sqrt(K_(sp))=sqrt(2.85xx10^(-13))=5.29x10^(-7)M` In solution concentration of each ion can be given as: Thus `[Ag^(+)]=(2sxx100)/(350)=(2xx1.52xx10^(-2)xx100)/(350)=0.869xx10^(-2)M` `[SO_(4)^(2-)]=(sxx100)/(350)=(1.52xx10^(-2)xx100)/(350)=0.43xx10^(-2)M` `[Pb^(2+)]=(s_(1)xx250)/(350)=(5.29xx10^(-7)xx250)/(350)=3.78xx10^(-7)M` `[CrO_(4)^(2-)]=(s_(1)xx250)/(350)=(5.29xx10^(-7)xx250)/(350)=3.78xx10^(-7)M` It is thus evidence that, `[Ag^(+)]^(2)[CrO_(4)^(2-)]=(0.869xx10^(-2))^(2)xx(3.78xx10^(-7))` `=2.85xx10^(-11)(gtK_(sp)Ag_(2)CrO_(4))` Thus `Ag_(2)CrO_(4)` will percipitate. |
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