Principles of Instrumental Analysis
7th Edition
ISBN: 9781305577213
Author: Douglas A. Skoog, F. James Holler, Stanley R. Crouch
Publisher: Cengage Learning
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Chapter 24, Problem 24.9QAP
Interpretation Introduction
Interpretation:
The percentage of
Concept introduction:
The Faraday’s law states that the quantity of electric change and mass of the substance is directly proportional to the amount of that substance liberated or deposited in the process of
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(Please give clear handwritten answer) 0.1 M HNO3 solution at 298K was electrolyzed in Hittorf cell using platinum electrodes. After electrolysis, 34.2 mg of copper was deposited in coulometer which in series with the Hittorf cell. 50 mL of HNO3 solution was withdrawn from anode compartment after electrolysis and found to have a concentration of 0.0821 M. [Atomic mass Cu = 63].
(i) Find the transference number of H + and NO3 −.
(ii) If 50 mL HNO3 solution was run off from cathode compartment, what would its concentration be?
A scientist was tasked to extract Fe from an aqueous suspension that contains 106 g of Fe2O3. The following steps detail the transformation of Fe2O3 (aq) to elemental iron:
I. Enough sulfur trioxide gas was bubbled to Fe2O3 aqueous suspension to completely yield ferric sulfate.
II. Then, 5.00 M nitric acid was added to ferric sulfate yielding an aqueous solution of ferric nitrate.
III. Excess magnesium powder was added to the aqueous solution of ferric nitrate precipitating the solid iron
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a. Write the balanced chemical reaction and the type of chemical reaction for [I], [II], [III]. Do not forget to indicate the states of the reactants and products (s, l, g).(CHOICES: COMBINATION, SINGLE DISPLACEMENT, DOUBLE DISPLACEMENT)
b. What is the final mass of iron? Express final answers in 3 significant figures.
c. High-concentration HCl is supposed to be added at the last part of the procedure. Briefly state its purpose.
Chapter 24 Solutions
Principles of Instrumental Analysis
Ch. 24 - Prob. 24.1QAPCh. 24 - Calculate the minimum difference in standard...Ch. 24 - Prob. 24.3QAPCh. 24 - Halide ions can he deposited at a silver anode,...Ch. 24 - What cathode potential (versus SCE) would be...Ch. 24 - Calculate the Lime required for a constant current...Ch. 24 - Calculate the time required for a constant current...Ch. 24 - Prob. 24.8QAPCh. 24 - Prob. 24.9QAPCh. 24 - A 0.0712-g sample of a purified organic acid was...
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