Chapter 1: Measurements/Matter
OBJECTIVES
1. Describe the role of chemists and some of the procedures that chemists use in their studies of matter and energy. (L1)
2. Distinguish between quantitative and qualitative measurements.
3. Distinguish between precision and accuracy. Give examples
4. Use significant digits correctly when recording data. Be able to perform mathematical calculations using significant digits.
5. List the basic SI units of measurements.
6. Differentiate between fundamental and derived units.
7. Be able to plot data using correct graphing techniques.
8. Define density and determine the density of a compound.
9. Use factor-label method to solve problems including converting units..
10. Define/describe matter, energy, and the different forms of energy.
11. State the Law of Conservation of Mass, Mass - Energy, and discuss its importance.
12. Classify matter; give examples of pure substances (elements, compounds), and mixtures.
13. Describe the properties and characteristics of elements, compounds and mixtures.
14. Differentiate between physical and chemical properties and changes. Give examples for each.
15. List examples of intensive and extensive properties.
16. Explain the meaning of a chemical formula ( symbols and subscripts)
17. Solve mole problems using factor-label method.
READING ASSIGNMENT
SECTION # / PAGES # / TOPIC1.2 / 7-15 / Measurements
1.3 / 15-18 / Properties of Substances: chemical, physical, density,solubility
1.1 / 2-7 / Types of matter
WRITTEN ASSIGNMENTS:
TOPIC / PAGE # / QUESTION(S) #Measurements / 23 / 12-18 even
Significant Figures / 24 / 20-30 even
Conversion Factors / 24 / 32-42 even
Types of Matter / 23 / 2-10 even
Physical and Chemical Properties / 25 / 44, 46, 48, 50, 52
Unclassified / 25 / 53, 54, 56, 58, 60
Conceptual Questions / 26 / 62, 64
Packet / 1-26 / As assigned
Scientific Notations
Express the following numbers in scientific notation. Keep three digits in your answers.
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Chapter 1: Measurements/Matter
1. 1930
2. 262,000
3. 71,400
4. 93,100,000
5. 704
6. 0.0713
7. 0.0000672
8. 26.1
9. 0.195
10. 7,790
11. 0.00000000833
12. 0.000 001 34
13. 55.6000
14. 2.940
15. 0.00621
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Chapter 1: Measurements/Matter
Evaluate the following and express the results in scientific notation. Keep two digits in your answer.
16. 8,200 x 510
17. 910 x 0.00030
18. 720 + 36,000
19. 3,100 +0.012
20. (240) (0.020)3
21. (0.0000080)1/3 (4.0)2
22. (2.6 x101)+(3.4 x 104)
23. (2.9x10-4)-(6.4x10-5)
24.
25.
26.
27.
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Chapter 1: Measurements/Matter
Accuracy and Precision
1. What is the difference between accuracy and precision?
2. Which student’s data are precise? Explain.
Student 1: 72.75 g; 73.49 g; 73.02 g; 73.25 g
Student 2: 72.01 g; 71.99 g; 72.00 g; 71.98 g
3. Using the balance that is improperly adjusted and always reads 0.50 grams too low, student obtained a mass of a beaker to be 50.62 g. The student than added some sugar to the beaker and using the same balance, obtained a total mass of 69.88 g. The student recorded the mass of the sugar as 19.26 g. Is the mass of the sugar inaccurate by 0.50 grams? Why or why not?
- Explain in your own words the range in heights that would be implied if you reported a measurement as “ His height is 182 cm.”
- Which of the following quantities could be determined exactly?
- Attendance at football game?
- Distance between goal posts at a football stadium?
- Number of grams in a sample of sugar?
- Number of inches in one yard?
- Your grade in this course?
6. Heather and Jason determined the density of a liquid three different times. The values they determined were 2.84 g/cm3, 2.85 g/cm3, and 2.80 g/cm3. The accepted value is known to be 2.40 g/cm3.
a. Are the values that Heather and Jason determined precise? Explain.
b. Are the values accurate? Explain.
c. Calculate the percent error and the uncertainty for each measurement.
7. During a dental work or minor surgery, a local anesthetic, such as procaine or lidocaine, is used to deaden the pain in a small area of the body. Although both are about equally effective in numbing the pain, procaine is eight times more toxic than lidocaine. With which anesthetic is it more important to be precise and accurate in administering a dose? Explain.
8. One method of chemical analysis compares the number of drops of reagent needed to react with a sample of known size and concentration to the number of drops of reagent needed to react with a sample the same size but of unknown concentration. In this method of analysis, the precision of each drop is more important than its accuracy. Explain.
9. When cutting the legs of a table to make it lower, precision is usually far more important than accuracy. Explain.
Significant Figures
1. Determine the number of significant digits and the uncertainty in each
of the following.
1. a. 6.751 g f. 30.07 g k. 54.52 cm3
b. 0.157 kg g. 0.106 cm l. 0.1209 m
c. 28.0 mL h. 0.0067 g m. 2.690 g
d. 2500 m i. 0.0230 cm3 n. 43.07 cm
e. 0.070 g j. 26.509 cm o. 6 352 001 g
Express each answer using correct significant digits.
2. Add.
a. 16.5 cm + 8 cm + 4.37 cm
b. 13.25 g + 10.00 g + 9.6 g
c. 2.36 m + 3.38 m + 0.355 m + 1.06 m
d. 0.0853 g + 0.0547 g + 0.037 g + 0.00387 g
3. Subtract.
a. 23.27 km - 12.058 km c. 350.0 m - 200 m
b. 13.57 g - 6.3 g d. 27.68 cm - 14.369 cm
4. Multiply
a. 2.6 cm x 3.78 cm d. 3.08 km x 5.2 km
b. 6.54 m x 0.02 m e. 3.15 dm x 2.5 dm x 4.00 dm
c. 0.036 m x 0.02 m f. 35.7 cm x 0.78 cm x 2.3 cm
5. Divide.
a. 35 cm2 / 0.62 cm d. 40.8 m2 / 5.050 m
b. 39 g/ 24.2 g e. 3.76 km/1.62 km
c. 0.58 dm3 / 2.15 dm f. 0.075 g/ 0.003 cm3
6. A piece of paper is 11.2 cm wide and 51 cm long. What is its area in square
centimeters? In square meters?
7. Using the following data: Mass of crucible + sample = 12.612 g
Mass of crucible alone = 11.5 g
Calculate the mass of the sample.
8. You start with a sample weighing 9.81 g and carry out the following operations in order.
State the number of grams remaining after each addition or subtraction.
a. Add 0.18-g b. Remove 9.220-g c. Add 1.83-g d. Add 6 g.
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Chapter 1: Measurements/Matter
Metric System- Vocabulary and Concepts (1)
1. List the SI base unit of measurement for these quantities:
a. time ______b. temperature ______
c. length ______d. mass ______
2. What is the symbol and meaning of these common metric prefixes?
a. milli ______b. deci ______c. centi ______
d. kilo ______e. micro ______
3. Match the approximate volume with each item.
a. an orange ______(1) 30 m3
b. a basketball ______(2) 200 cm3
c. a small van ______(3) 20 L
d. an aspirin tablet ______(4) 200 mm3
4. List these units in order from largest to smallest. ______
a. 1 dm3 b. 1 L c. 1 mL d. 1L e. 1 cL f. 1 dL
5. Match the prefixes with their equivalents. Write the letter of the correct value on the space provided.
______1. nano A. 1/1000 (thousandth)
B. 1000 ( thousand)
______2. centi C. 1/10 (tenth)
D. 1/ 1 000 000 ( millionth)
______3. kilo E. 1/ 1 000 000 000 ( billionth)
F. 1/100 ( hundredth)
______4. deci G. 10 (ten)
______5. milli
______6. micro
6. List the basic SI units and abbreviation for each of the following quantities.
Quantity SI Unit Abbreviation
length ______
mass ______
volume ______
area ______
density ______
time ______
Derived and Fundamental Units (Optional)
1. Express the following derived units in terms of the base SI units listed I Table 1 in Appendix 1 (page A.1). Example: 1 cm3 = 1 x 10-6 m3
a. milliliter b. km3 c. dm2 d. liter
e. joule f. Newton g. Pascal h. mm2
In the following equations, substitute the appropriate units for the symbols and find the units of the missing left-hand member.
s , distance in meters v, velocity in m/sec a, acceleration in m/sec2
t, time in sec m (mass) in kg F in newtons or kg-m/sec2
2. ? = vt 3. ? = at 4. ? = at2 5. ? = v/a
6. ?2 = as 7. ? = mv2/s 8. ? = ma 9. ? = mv/F
10. ? = 4π2ms/t2 11. ? = Ft2/4π2m 12. ? = 2(s-vt)/t2 13. ?2 = 4π2ms/F
Use the following nonsense units and solve the following for the left-handed member of the equation.
a= 1 club b = 1 bang c = 1 tic
14. d = b/c 15. e = d/c 16. m = ec2 17. d2 = eb
18. g = ab2/c2 19. g = aeb 20. h = g/c 21. e = d2/b
22. x = 23. k = gb/a2
24. The electric force between two charged objects is expressed as a
F = k
F is the force in newtons, Q1 and Q2 are charges in coulombs, and R is the distance between the charges expressed in meters. What units must k have to make this formula dimensionally correct (correct units)?
25. Which of the following equations cannot be correct because of dimensional inconsistencies? In each case, s is the distance measured in meters; v is the velocity measured in meters/seconds; a is the acceleration in units of m/sec2; and t is the time measured in seconds.
a. s = vt + 3at2
b. v = v2 - ½ as2
c. s + ½ at2 = vt
d. at2 = 2(s2/t3)
1. a) 1x10-6 m3 b) 1x109m3 c)1x10-2 m2 d) 1 x10-3 m3 e) (kgm2)/s2 f) kgm/s2 g) kg/(ms2)
h) 1x10-6 m2
2. m 3. m/sec 4. m 5. sec 6. m/sec
7. Newton 8. Newton 9. sec 10. kg m/s2 11. m 12. 0
13. sec 14. 1 bang/tic 15. 1 bang/tic2 16. 1 bang 17. 1 bang/tic 18. 1 club x bang2/tic2
19. 1 club x bang2/tic2 20. 1 club x bang/tic3 21. 1 bang/tic2 22. (bang tic)1/2
23. 1 club3 x bang3/tic2 24. (kgm3)/(s2C2) 25. a) yes; b) no; c) yes; d) no
Metric System Conversions
I. Convert the following measurements to milligrams:
1. 135.4 g ______3. 165.3 dg ______
2. 0.00238 g ______4. 3.01 x 10 -6 cg ______
II. Convert the following measurements to centigrams:
5. 938 mg ______7. 19.3 g ______
6. 0.31 kg ______8. 8.5 dg ______
III. Convert the following measurements to decigrams:
9. 142.81 g ______11. 36.9 mg ______
10. 0.895 kg ______12. 0.041 g ______
IV. Convert the following measurements to grams:
13. 41.4 cg ______15. 14.587 mg ______
14. 329 mg ______16. 0.01456 kg ______
V. Convert the following measurements to kilograms:
17. 2450 g ______19. 283 mg ______
18. 147.2 hg ______20. 2.4 x 106 dg ______
VI. Convert the following measurements to liters:
21. 182 mL ______23. 22.9 cm3 ______
22. 0.895 kL ______24. 4.2 dm3 ______
VII. Convert the following measurements to milliliters:
25. 14.2 L ______27. 148 cm3 ______
26. 2.5901 L ______28. 0.416 L ______
VIII. Convert the following measurements to millimeters:
29. 16 m ______31. 234.5 km ______
30. 85.4 cm ______32. 14.2 dm ______
IX. Convert the following measurements to centimeters:
33. 3.67 dm ______35. 124 mm ______
34. 0.85 m ______36. 85.9 km ______
X. Convert the following measurements to decimeters:
37. 14.5 m ______38. 1.4 x 10-4 cm ______
XI. Convert the following measurements to meters:
39. 1.0 cm ______41. 39.0 dm ______
40. 1.0 x 10-9 mm ______42. 2.67 Mm ______
XII. Convert the following to kilometers: ( 1 in = 2.54 cm; 1 foot = 12 inches)
43. 23.896 cm ______
44. 562.0 Gm ______
45. 7.4 dm ______
Answers:
1.1.354 x 105mg 2. 2.380 mg 3. 1.653 x 104 mg 4. 3.01 x 10-5 mg 5. 9.38 x 101 cg
6. 3.1 x 104 cg 7. 1.93 x 103 cg 8. 8.5 x 101 cg 9. 14.281 dg 10. 8.95 x 103 dg
11. 3.69 x 10-1 dg 12. 4.1 x 10-1 dg 13. 4.14 x 10-1 g 14. 3.29 x 10-1 g
15. 1.4587 x10-2 g 16. 1.456 x 101g 17. 2.450 kg 18. 1.472 x 101 kg
19. 2.83 x 10-4 kg 20. 2.4 x 102 kg 21. 1.82 x 10-1 L 22. 8.95 x 102 L
23. 2.29 x 10-2 L 24. 4.2 L 25. 1.42 x 104 mL 26. 2.5901 x 103 mL
27. 1.48 x 102 mL 28. 4.16 x 102 mL 29. 1.6 x 10-2 mm 30. 8.54 x 102 mm
31. 2.345 x 108 mm 32. 1.42 x 103 mm 33. 3.67 x 101 cm 34. 8.5 x 101 cm
35. 1.24 x 101 cm 36. 8.59 x 106 cm 37. 1.45 x 102 dm 38. 1.4 x 10-5 dm
39. 1.0 x 10-2 m 40. 1.0 x 10-12 m 41. 3.90 m 42. 2.67 x 106 m
43. 2.3896 x 10-4 km 44. 5.62 x 108 km 45. 7.4 x 10-4m
Dimensional Analysis(#1)
1. What are the two conversion factors for each pair of units?
a. kilometers and meters
b. grams and centigrams
c. grams of water and milliliters of water ( density 1 g = 1 milliliter)
d. inches and feet
e. kilograms and grams
f. dollars and nickels.
Solve using dimensional analysis ( factor label method).
2. How many millimeters are equal to 5.43 meters?
3. How many kilograms in 32 500 grams?
4. Convert 45.3 kcal to calories.
5. A 1oC increase on the Celsius scale is equivalent to 1.8o increase on the Fahrenheit scale. If the temperature decreased 85.4 oF, what is the corresponding temperature drop on the Celsius scale?
6. One of the first dental amalgams, used for tooth fillings, consisted of 26.0 g of silver, 10.8 g of tin, 2.40 g of copper, and 8.00 x 10-1 g of zinc. How much silver is in a 15.0-g sample of this amalgam?( Note: you need to find the total mass of the sample to write the conversion factor.)
Use the given densities to make the following conversions.
7. 23.6 g of boron to cm3 of boron ( density of boron = 2.34 g/cm3)
8. 1.4 L of argon to g of argon ( density of argon = 1.78 g/L)
9. 8.96 g of mercury to cm3 of mercury ( density of mercury = 13.5 g/cm3 )