Discussion [Objectives and content of the introductory course in

Discussion [Objectives and content of the introductory course in quantitative analysis]. W. D. Collins. J. Chem. Educ. , 1928, 5 (8), p 963. DOI: 10.1...
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VOL. 5. No. 8

OBJECTIVESAND CONTENT OR COURSEI N ANALYSIS

963

DISCUSSION E

In the teaching of analytical chemistry, and to some extent in the teaching of any other kind of chemistry, the quality of the chemicals used is of the greatest importance. I t is well known that confusion of students often results from the use of chemicals that contain impurities which will interfere with tests in qualitative analysis and give incorrect results in quankitative analysis. The cost of the best reagent chemicals is so little more than the cost of the poorest that the money saved to one student by buying inferior chemicals almost vanishes. If the time of the student is given any cash value, which those who pay the bills for his subsistence and attendance a t college generally feel to be somewhat higher than nothing per day, there is a decided loss in the use of poor chemicals which may cause waste of time. Accounts from four government laboratories in 1924 indicated a total expenditure of $7360 for the chemicals used by workers whose salaries amounted to $335,000 for the year. Assuming 300 working days in the year the total cost of chemicals was equivalent t o the salaries for about 6.5 days. It is easy to lose a day or two of time through the use of a poor reagent or the work of purifying it. A few days lost will more than balance any money saved by buying poor materials. It is dangerous to have poor chemicals around even though they are perfectly satisfactory for many uses. With hu-

man nature as it is the poor ones will be used a t times when the better grade is hardly good enough. One help in getting satisfactory reagents is to specify that they shall meet the specifications of the Committee on Analytical Reagents of the American Chemical Society and then test all deliveries to see that the specificationsare met.