Table 1.3. Effect of fingerprints in weighing. Condition Mass (g) Mass of beaker using crucible tongs 30.145 Mass of beaker handled with bare hands 30.149 Post lab Q1. Based on the above observations, what can be concluded about the effect of fingerprints on weighing objects? Suggest other means of weighing without making use of bare hands aside from using crucible tongs. Post lab Q2. Why must the following precautions be observed when using an analytical balance? a. Balance door must be closed while weighing b. Objects must not be weighed hot c. Bubble must be at the center d. Do not lean on the table carrying the balance

Table 1.3. Effect of fingerprints in weighing. Condition Mass (g) Mass of beaker using crucible tongs 30.145 Mass of beaker handled with bare hands 30.149 Post lab Q1. Based on the above observations, what can be concluded about the effect of fingerprints on weighing objects? Suggest other means of weighing without making use of bare hands aside from using crucible tongs. Post lab Q2. Why must the following precautions be observed when using an analytical balance? a. Balance door must be closed while weighing b. Objects must not be weighed hot c. Bubble must be at the center d. Do not lean on the table carrying the balance

Principles of Modern Chemistry

8th Edition

ISBN:9781305079113

Author:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

Publisher:David W. Oxtoby, H. Pat Gillis, Laurie J. Butler

ChapterA: Scientific Notation And Experimental Error

Section: Chapter Questions

Problem 8P

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