Assume that the conductivity of a solution depends only on the total concentration of dissolved ions and that you measure the conductivity of three different solutions while performing titrations in which
I.50.00 mL of 0.100 M aqueous CH 3 CO 2 H is titrated by addition of 0.100 M NaOH.
II.50.00 mL of 0.100 M aqueous NaBr is titrated by addition of 0.100 M AgNO 3 .
III.50.00 mL of 0.100 M aqueous CaCl 2 is titrated by addition of 0.100 M Na 2 CO 3 .
-Which of the above graphs corresponds to titration III?
A)graph (1)
B)graph (2)
C)graph (3)
D)None of the graphs

Question

Assume that the conductivity of a solution depends only on the total concentration of dissolved ions and that you measure the conductivity of three different solutions while performing titrations in which
I.50.00 mL of 0.100 M aqueous CH 3 CO 2 H is titrated by addition of 0.100 M NaOH.
II.50.00 mL of 0.100 M aqueous NaBr is titrated by addition of 0.100 M AgNO 3 .
III.50.00 mL of 0.100 M aqueous CaCl 2 is titrated by addition of 0.100 M Na 2 CO 3 . 
-Which of the above graphs corresponds to titration III?
A)graph (1) 
B)graph (2) 
C)graph (3) 
D)None of the graphs

Quizplus · Accepted Answer

Titrations III involves the reaction between CaCl2 and Na2CO3. The balanced equation is CaCl2 + Na2CO3 → CaCO3 + 2NaCl. During this titration, the concentration of total dissolved ions in the solution increases as more Na2CO3 is added. This leads to an increase in conductivity until the equivalence point, at which all CaCl2 has reacted with Na2CO3 and the conductivity drops sharply. Graph C shows this characteristic pattern of conductivity increasing until the equivalence point, at which point it drops sharply. Graphs A and B do not show this pattern and are therefore not representative of titration III.

Assume That the Conductivity of a Solution Depends Only on the Total