Lcolvin.weebly.com



Measurement and Significant FiguresActivity 2Activity 2: Sig Fig RulesStudy the examples on the three Sig Fig Cards. Look for patterns and see if you can figure out the rules for when a number is significant. STARRChart Rules When are nonzero numbers significant?_______ 1. When are zeros significant?_______ 1._______ 2. When are zeros NOT significant?_______ 1._______ 2.Look at your STAAR Reference Chart and find the “Rules for Significant Figures”. The first three rules correspond to the rules you figured out from the cards. Do any of the rules on the STAAR Reference Chart agree with the rules you figured out? Place the corresponding number of the STAAR chart rules (1, 2, or 3) in the blanks to the left of your rules. (STAAR rules can be used more than once.)Determine the number of significant figures in the following numbers:1. 4.53 __________6. 0.070 __________2. 2.30 __________ 7. 0.707 __________3. 1.02 __________ 8. 7.070 __________4. 4500 __________ 9. 7070 __________5. 3200. __________ 10. 700 __________Use a calculator to perform the following calculation: 52 ÷ 2.356Record your answer EXACTLY as it appears in the calculator: ________________You have just experienced CALCULATOR VOMIT! Many beginning chemistry students have fallen victim to calculator vomit. Fortunately, there is a cure. Follow the following two calculation rules and DON’T fall prey to calculator vomit!Rule 1 – Multiplication and Division: Determine the number of sig figs in each number that is multiplied or divided. Round the answer to the lowest number of sig figs. Ex. 23.0 x 2.45897 = 56.55631 = 56.6 3sf 6sf vomit! 3sfRule 1 – Addition and Subtraction: Determine the number of decimal places in each number that is added or subtracted. Round the answer to the lowest number of decimal places. Ex. 43.55 + 23.6543 = 67.2043 = 67.20 2dp 4dp vomit! 2dpPerform the following calculations. Round the answers to the correct number of digits as indicated by the two rules above.3.4 x 2.32 =6. 3.890/121 =4.5 + 2.3 =7. 6.00 + 3.411 =7.77/2.3 =8. 1200 x 23.4 =4.5 – 5 = 9. 78.5 + 0.0021 + 0.0099 =120 x 0.0002 =10. 6.4432/12 = ................
................

In order to avoid copyright disputes, this page is only a partial summary.

Google Online Preview   Download