The concentration of Ca²+ in a sample of sea water is determined using a Ca ion-selective electrode and a one-point standard addition. A 10.00-mL sample is transferred to a 100-mL volumetric flask and diluted to volume. A 50.00-mL aliquot of the sample is placed in a beaker with the Ca ISE and a reference electrode, and the potential is measured as -0.05290 V. After adding a 1.00-mL aliquot of a 5.00 × 10-2 M standard solution of Ca²+ the potential is -0.04417 V. What is the concentration of Ca²+ in the sample of sea water?

The concentration of Ca²+ in a sample of sea water is determined using a Ca ion-selective electrode and a one-point standard addition. A 10.00-mL sample is transferred to a 100-mL volumetric flask and diluted to volume. A 50.00-mL aliquot of the sample is placed in a beaker with the Ca ISE and a reference electrode, and the potential is measured as -0.05290 V. After adding a 1.00-mL aliquot of a 5.00 × 10-2 M standard solution of Ca²+ the potential is -0.04417 V. What is the concentration of Ca²+ in the sample of sea water?

Chemistry: The Molecular Science

5th Edition

ISBN:9781285199047

Author:John W. Moore, Conrad L. Stanitski

Publisher:John W. Moore, Conrad L. Stanitski

Chapter17: Electrochemistry And Its Applications

Section: Chapter Questions

Problem 92QRT

See similar textbooks

Similar questions

For each of the reactions, calculate E from the table of standard potentials, and state whether the reaction is spontaneous as written or spontaneous in the reverse direction under standard conditions. (a) Zn(s)+Fe2+(aq)Zn2+(aq)+Fe(s) (b) AgCl(s)+Fe2+(aq)Ag(s)+Fe3+(aq)+Cl(aq) (c) Br2(l)+2Cl(aq)Cl2(g)+2Br(aq)
Halide ions can he deposited at a silver anode, the reaction being Ag(s) + X- AgX(s) +e- Suppose that a cell was formed by immersing a silver anode in an analyte solution that was 0.0250 M Cl-,Br-, and I -ions and connecting the half-cell to a saturated calomel cathode via a salt bridge. (a) Which halide would form first and at what potential? Is the cell galvanic or electrolytic? (b) Could I- and Br- be separated quantitatively? (Take 1.00 l0-5 M as the criterion for quantitative removal of an ion.) If a separation is feasible, what range of cell potential could he used? (c) Repeat part (b) for I- and Cl-. (d) Repeat part (b) for Br- and Cl-.
The measurement of pH using a glass electrode obeys the Nernst equation. The typical response of a pH meter at 25 00C is given by the equation where contains the potential of the reference electrode and all other potentials that arise in the cell that are not related to the hydrogen ion concentration. Assume that = 0.250 V and that a. What is the uncertainty in the values of pH and [H+] if the uncertainty in the measured potential is 1 m V ( 0.001 V)? b. To what precision must the potential be measured for the uncertainty in pH to be 0.02 pH unit?
An alloy made up of tin and copper is prepared by simultaneously electroplating the two metals from a solution containing Sn(NO3)2 and Cu(NO3)2.If 20.0% of the total current is used to plate tin, while 80.0% is used to plate copper, what is the percent composition of the alloy?
From the standard potentials Tl++eTl(s)E0=0.336V TlCl(s)+eTl(s)+ClE0=0.557V calculate the solubility product constant for TlCl.
A 0.0712-g sample of a purified organic acid was dissolved in an alcohol-water mixture and titrated with coulometrically generated hydroxide ions. With a current of 0.0392 A, 241 s was required to reach aphenolphthalein end point. Calculate the equivalent mass of the acid.
From the standard potentials Ag2SeO4(s)+2e2Ag(s)+SeO42-E0=0.355V Ag++2eAg(s)E0=0.799V calculate the solubility product constant for Ag2SeO4.
Calculate the standard cell potential of the following cell at 25C. Sn(s)Sn2+(aq)I2(aq)I(aq)