[Transcriber's notes: In the chemical equations, superscripts are indicated with a ^ and subscripts are indicated with a _. The affected item is enclosed in curly brackets {}. Examples are H^{+} for hydrogen ion and H_{2}O for water. Since the underscore is already being used in this project, italics are designated by an exclamation point before and after the italicized word or phrase.]
AN INTRODUCTORY COURSE
OF
QUANTITATIVE
CHEMICAL ANALYSIS
WITH
EXPLANATORY NOTES
BY
HENRY P. TALBOT
PROFESSOR OF INORGANIC CHEMISTRY AT THE MASSACHUSETTS INSTITUTE OF TECHNOLOGY
SIXTH EDITION, COMPLETELY REWRITTEN
PREFACE
This Introductory Course of Quantitative Analysis has been prepared to meet the needs of students who are just entering upon the subject, after a course of qualitative analysis. It is primarily intended to enable the student to work successfully and intelligently without the necessity for a larger measure of personal assistance and supervision than can reasonably be given to each member of a large class. To this end the directions are given in such detail that there is very little opportunity for the student to go astray; but the manual is not, the author believes, on this account less adapted for use with small classes, where the instructor, by greater personal influence, can stimulate independent thought on the part of the pupil.
The method of presentation of the subject is that suggested by Professor A.A. Noyes' excellent manual of Qualitative Analysis. For each analysis the procedure is given in considerable detail, and this is accompanied by explanatory notes, which are believed to be sufficiently expanded to enable the student to understand fully the underlying reason for each step prescribed. The use of the book should, nevertheless, be supplemented by classroom instruction, mainly of the character of recitations, and the student should be taught to consult larger works. The general directions are intended to emphasize those matters upon which the beginner in quantitative analysis must bestow special care, and to offer helpful suggestions. The student can hardly be expected to appreciate the force of all the statements contained in these directions, or, indeed, to retain them all in the memory after a single reading; but the instructor, by frequent reference to special paragraphs, as suitable occasion presents itself, can soon render them familiar to the student.
The analyses selected for practice are those comprised in the first course of quantitative analysis at the Massachusetts Institute of Technology, and have been chosen, after an experience of years, as affording the best preparation for more advanced work, and as satisfactory types of gravimetric and volumetric methods. From the latter point of view, they also seem to furnish the best insight into quantitative analysis for those students who can devote but a limited time to the subject, and who may never extend their study beyond the field covered by this manual. The author has had opportunity to test the efficiency of the course for use with such students, and has found the results satisfactory.
Table of contents (by pages)
- 1: An Introductory Course of Quantitative Chemical An
- 2: Massachusetts Institute of Technology
- 3: GRAVIMETRIC ANALYSISGENERAL DIRECTIONS Precipitation
- 4: Volumetric methods are generally more rapid
- 5: Is or can be demanded of a quantitative analyst
- 6: Or the amount of reagents required
- 7: The processes of volumetric analysis are easily classified
- 8: And the unused excess determined by titration
- 9: To the nearest 5 or 10 milligrams
- 10: 20 and 10 milligram weights combined
- 11: If the burette has a glass stopcock
- 12: Two divisions below the meniscus
- 13: CALIBRATION OF THE BURETTESTwo burettes
- 14: Or it may be a miniature burette
- 15: Pipettes are usually already graduated when purchased
- 16: Mark the location of the lowest point of the meniscus
- 17: In connection with the normal solution
- 18: Of sodium and potassium hydroxide
- 19: Methyl orange and phenolphthalein will be taken as types
- 20: Hydrolyzed to a considerable extent
- 21: Is titrated against a strong base
- 22: Soluble litmus tablets are often obtainable
- 23: Return the beaker to the acid burette
- 24: Refill the burettes and repeat the titration
- 25: Note the readings of the burettes after the proper interval
- 26: Potassium tetroxalate KHC 2 O 4
- 27: Add two drops of phenolphthalein solution
- 28: Methyl orange and phenolphthalein
- 29: Hypochlorites and arsenious acid
- 30: Pulverize about 28 grams of ferrous sulphate FeSO 4
- 31: After applying corrections for burette readings
- 32: Such as ferrous ammonium sulphate
- 33: Of these stannous chloride acts most readily
- 34: Calculate the percentage of iron Fe in the limonite
- 35: The ferric hydroxide remains undissolved
- 36: Potassium permanganate has an intense coloring power
- 37: Comparison of permanganate and ferrous solutionsprocedure
- 38: Zinc or stannous chlorides are the most satisfactory agents
- 39: Of the dilute acid after the reductor is well washed
- 40: Note 5 The potassium permanganate may
- 41: Determination of iron in limonite
- 42: Of the manganous sulphate titrating solution Note 1
- 43: Note 4 Ferrous ammonium sulphate
- 44: Which oxidize the thiosulphate
- 45: Comparison of iodine and thiosulphate solutionsprocedure
- 46: Titrate to the disappearance of the iodo starch blue
- 47: Calculate the similar value for the thiosulphate solution
- 48: Erlenmeyer flasks or small beakers
- 49: Cover the beakers and pour over the stibnite 5 cc
- 50: CHLORIMETRY The processes included under the term
- 51: Which liberates the weak hypochlorous acid
- 52: Or 4 grams of ammonium thiocyanate
- 53: Collection of the hydroxide upon a filter
- 54: The filters employed should be washed filters
- 55: The vessels which contain the initial filtrate should
- 56: But for most purposes the calcium chloride
- 57: PREPARATION OF CRUCIBLES FOR USEAll crucibles
- 58: Elsewhere than into the beaker
- 59: Suspend some finely divided asbestos
- 60: And in concentrated nitric acid
- 61: Deduct the weight of the crucible
- 62: Of dilute hydrochloric acid sp
- 63: Indicating the presence of ferric iron
- 64: Note 2 Ignited ferric oxide is somewhat hygroscopic
- 65: The most important properties of these hydroxides
- 66: And including the barium chloride used as the precipitant
- 67: Determination of sulphur in barium sulphate procedure
- 68: And the barium carbonate insoluble
- 69: Of molybdate solution to the nitrate
- 70: Partially separate with the phosphomolybdate
- 71: As it is necessary to purify it by reprecipitation
- 72: Containing varying amounts of magnesium
- 73: 1 milligram when the sample taken weighs 0
- 74: Again add ammonium hydroxide in slight excess
- 75: Of dilute ammonium hydroxide sp
- 76: Calcium oxalate is nearly insoluble in water
- 77: Of a solution of disodium phosphate
- 78: Determination of carbon dioxide
- 79: Both combine with carbon dioxide to form carbonates
- 80: Close the pinchcocks a and k and open h
- 81: And to be discharged by that electrode
- 82: And hence fewer ions approach the electrodes
- 83: The number of coulombs required to deposit 107
- 84: And again electrolyze with clean electrodes Note 7
- 85: Probably in the form of PbO 2 ions
- 86: Of a dilute solution of litmus Note 1
- 87: The asbestos washed thoroughly
- 88: Such as meta silicic acid H 2 SiO 3
- 89: Dehydration and filtrationprocedure
- 90: The insoluble silica is filtered
- 91: The molecular weight of BaSO 4 is 233
- 92: Each acting as an oxidizing agent against ferrous sulphate
- 93: The weight of KCl is found by subtracting this from 0
- 94: 1063 equivalents of hydrochloric acid in 976 cc
- 95: Given the following data 1 cc
- 96: 5 N required for phenolphthalein end point
- 97: Of water must be added to 1000 cc
- 98: Using phenolphthalein as an indicator
- 99: Of ferrous sulphate solution 80 grams FeSO 4
- 100: A solution contains 50 grams of KHC 2 O 4
- 101: Reduced and titrated with KMnO 4
- 102: Calculate the log factor for a Pb in PbCrO 4
- 103: How many cubic centimeters of ammonium hydroxide sp
- 104: Shall equal the percentage of CaO in the sample
- 105: C Calculate the weight of PbSO 4
- 106: Electrolytic Dissociation Theory
- 107: Although not in direct proportion
- 108: A quantitative study of the amount of undissociated acid
- 109: Thus altering their concentrations
- 110: More of the AgNO 3 dissociates
- 111: As the undissociated oxalic acid forms
- 112: To the right and crease evenly
- 113: Date DETERMINATION OF COMPARATIVE STRENGTH HCl vs
- 114: 6915 Constant weights 14
- 115: 1 molal solution Nitric acid sp
- 116: They are sufficiently accurate for use in chemical analyses
- 117: In limestone Chlorimetry Chlorine
