Chem 1100 study guide answers ch 1 PDF

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Download Chem 1100 study guide answers ch 1 PDF

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Chapter One Study Guide (1.4-1.6) Answers Outline I. Measurements A. Units 1. SI system of units (length, mass, time, energy, temperature)

2. Prefixes

B. Errors 1. Systematic

2. Random

3. Blunders

4. Propagation of Errors a. Addition and Subtraction

b. Multiplication and Division

C. Significant Figures 1. What numbers are significant

2. What numbers are NOT significant

3. How do we apply significant figures in calculations a. Addition and Subtraction

b. Multiplication and Division

D. Scientific Notation

II. Scientific Method A. Observation and Question B. Hypothesis C. Experimentation D. Theory

II. Definitions A. Accuracy B. Precision III. The factor-label method (dimensional analysis)

IV. Conversion of Kelvin and Celsius and Fahrenheit

Practice Problems 1. Solve the following problems and give the answer with the correct number of significant figures. a. 36.42 + 0.0702 = 36.49 b. 43000 X 300.0 = 13,000,000 or 1.3 x 10^7 2. If a car is going 72 kilometers per hour, how fast is it going in cm/sec? a. 200 cm/sec b. 1200 cm/sec c. 2.0 x 10^3 cm/sec d. 1.2 x 10^4 cm/sec e. None of the above

3. Which of the following is the smallest mass? a. 25 kg b. 2.5 x 10^-2 Mg c. 2.5 x 10^15 pg d. 2.5 x 10^9 fg e. 2.5 x10^10 ng 4. Which of the following is incorrectly labeled? a. 2.3 x 10^-12 m = 2.3 pm b. 2.8 x 10^3 g = 4.8 kg c. 4.8 x 10^-6 mL = 4.8 microliters d. 5.8 x 10^-9 s = 5.8 ns 5. Which of the following common objects weighs closest to 1 gram? a. a baseball b. a chicken egg c. a shirt button d. a postage stamp e. a human hair 6. What is the correct answer (reported to the proper number of significant figures) to the following? 6.3 x 3.25 = ________ a. 20 b. 20.475 c. 20.48 d. 20.5 e. 21 7. What is the correct answer (reported to the proper number of significant figures) to the following? (2115 – 2101) x (5.11 x 7.72) = _________ a. 552 b. 552.29 c. 552.3 d. 5.5 x 10^2 e 6 x 10^2 8. How many significant figures are there in the number 0.00230? a. 2 b. 3 c. 4 d. 5 e.6

9. How many liters of air are in a room that measures 10.0 ft x 11.0 ft and has an 8.00 ft x 3 ceiling? (1 inch = 2.54 cm; 1 liter = 10^3 cm ) a. 2.49 x 10^4 b. 92.8 c. 26.8 d. 2.68 x 10^7 e. 8.84 x 10^5 10. What is the mass (in g) of an object that has a volume of 18.9 cm 3 and a density of 3.450 g/cm3?

11. (0.002842)(12.80184) = _____________ 0.00032 a. 113.73635 b. 113.736 c. 113.74 d. 113.7 e. 1.1 x 10^2 12. Convert 0.003002 to standard scientific notation. a. 3002 x 10^6 b. 3.002 x 10^-3 c. 3.002 x 10^3 d. 3002 x 10^-6 13. Which of the following is the lowest temperature? a. 313 K b. 54º F c. 37º C d. All these temperatures are equal 14. Convert 100 cm3 to m3. a. 1 x 10^0 m3 b. 1 x 10^-4 m3 c. 1 x 10^4 m3 d. 1 x 10^8 m3 15. How many significant figures are there in the answer for the following problem? [(131.7 – 119) x 1.05] = ? 0.500 a. one b. two c. three

d. four 16. What is the stoichiometric coefficient for oxygen when the following equation is balanced using the lowest whole-number coefficients? ______ C3H8O (l) + ______ O 2 (g) Æ ______ CO2 (g) + H2 O (l) a. 7 b. 9 c. 3 d. 5...