CHM 1025C Name: _________________Section: MW or
TR
Introduction
to Measurement: Lab #2
Post Lab Report/Problems
Read the section on “Significant Figures,” via the Handout by Dr. David Summer or read Section 2.1 through 2.7 of Chapter 2 of the Corwin textbook, then solve the following problems. Hand this page in after performing the lab activities with you data and calculation no later than the beginning of the following lab session..
1. Write the correct number of significant figures for each of the following readings. If the number of significant figures is unclear (ambiguous), say so. If the number is exact, say so..
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(a) |
70,503 kg |
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(b) |
67,000,000 m |
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(c) |
0.00847 g |
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(d) |
4.826 x 10-5 sec |
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(e) 1000 mL = 1 L __________________
(f) 1,200,000 people __________________
2. Perform the following operations, reporting the answers with the correct number of significant figures.
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(a) |
38.904 + 196.63 + 48 + 1.0648 |
= |
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(b) |
34.068 – 12.8 |
= |
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(c) |
41.8 x 2.1 |
= |
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(d) |
(1.412 x 103) x (2.60 x 10-4) |
= |
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(e) |
42.31 / 0.040 |
= |
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3. The Nine Penny Problem: You are given 2008 pennies, one 1980 penny, and a platform balance (A balance where you place objects to compare mass on both sides.)
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The 2008 pennies (2.50 gram each) each weight about one half gram less than the 1980 penny (slightly over 3.00 grams). Can you devise a method for determining the heavy penny in only TWO weighings?