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What Is The Total Molar Concentration of Ions?

What is the total molar concentration of ions in each of the following solutions? Assuming complete dissociation.

1.)   .750 M of K2CO3

2.)   .355 M of AlCl3

 

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What Is The Mass Percent?

A sample weighing 14.98g and containing a small amount of copper was treated to give a solution containing aqueous Cu^2+ ions.  Sodium iodide was then added ti yield solid copper (I) iodide plus I3^- ion, and the I3^- was titrated with thiosulfate, S2O3^2-.  The titration required 10.49mL of .100M Na2S2O3 for complete reaction.  What is the mass percent copper in the sample?  The balanced equations are…

2Cu^2+(aq)+5I^-(aq)—->2CuI(s)+I3^-(aq)

I3^-(aq)+2S2O3^2-(aq)—->3I^-(aq)+S4O6^2-(aq)

What Is The Mass Percent?

The metal content of iron in ores can be determined by a redox procedure in which the sample is first oxidized with Br2 to convert all the iron to Fe^3+ and then titrated with Sn^2+ to reduce the Fe^3+ to Fe^2+.  The balanced equation is:

2Fe^3+(aq)+Sn^2+(aq)—->2Fe^2+(aq)+Sn^4+(aq)

What is the mass percent of Fe in a .1875g sample of ore if 13.28mL of a .1015M Sn^2+ solution is needed to titrate the Fe^3+?

What Is The Molar Concentration?

What is the molar concentration of As(III) in a solution if 22.35mL of .100M KBrO3 is needed for complete reaction with 50.00mL of the As(III) solution?  The balanced equation is…

3H3AsO3(aq)+BrO3^-(aq)—->Br^-(aq)+3H3AsO4(aq)

What Is The Concentration?

Dichromate ion, Cr2O7^2-, reacts with aqueous iron(III) ion in acidic solution according to the balanced equation

Cr2O7^2-(aq)+Fe^2+(aq)+14H^+(aq)—->2Cr^3+(aq)+6Fe^3+(aq)+7H20(l)
 
What is the concentration of Fe^2+ if 46.99mL of .2004M K2Cr2O7 is needed to titrate 
50.00mL of the Fe^2+ solution?
 

Molar Concentration

What is the molar concentration of Br^- ions in a 0.225M (aq) solution of FeBr3, assuming complete dissociation?

Molar Concentration

What is the molar concentration of As(III) in a solution if 25.35mL of 0.110MKBrO3 is needed to titrate 53.55mL of the As(III) solution? The balanced equation is
3H3AsO3(aq)+BrO−3(aq)→Br−(aq)+3H3AsO4(aq)

Concentration

Iodine, I2, reacts with aqueous thiosulfate ion in neutral solution according to the balanced equation I2(aq)+2S2O2−3(aq)→S4O2−6(aq)+2I−(aq).

How many grams of I2 are present in a solution if 40.00mL of 0.150M Na2S2O3solution is needed to titrate the I2solution?

Molar Concentrations

Titration with solutions of potassium bromate, KBrO3, can be used to determine the concentration of As(III).

What is the molar concentration of As(III) in a solution if 25.35mL of 0.110M KBrO3 is needed to titrate 53.55mL of theAs(III) solution? The balanced equation is
3H3AsO3(aq)+BrO−3(aq)→Br−(aq)+3H3AsO4(aq)

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