Chapter 3: Scientific Measurement
Section 3.1 Measurements and Their Uncertainty (pg.63-72)
1. Write numbers in scientific notation and perform calculations with and without a calculator. Refer to Appendix C (Math Handbook) pp R56-R57.
2. Distinguish between accuracy and precision. Relate to error and deviation.
3. Calculate error and percent error of an experimentally determined measurement.
4. Identify the number of significant digits in a recorded measurement.
5. Apply the rules for significant figures (SIG FIGS) in calculations to report answers correctly.
Refer to Appendix C (Math Handbook) pp R59-R60.
Section 3.2 The International System of Units (pg. 73-79)
1. Be familiar with the basic SI units and symbols for length, mass, temperature, and time as well as the more commonly used non SI units..
2. Convert between Celsius and Kelvin temperature scales.
3. Relate metric prefixes, from pico-to giga- as multiples of ten (your book only provides values for nano- to kilo-).
4. Equate the milliliter and the cubic centimeter.
5. Distinguish mass from weight.
Section 3.4 Density (pg. 89-93)
1. Describe the relationship between mass, volume, and density
2. Calculate mass, volume or density from experimental data and give the answer to the correct number of significant figures.
Bunsen Burner Lab Objectives
1. Distinguish between a luminous flame and a Bunsen flame.
2. Explain how methane combines with oxygen in the burner resulting in complete and incomplete combustion.
3. Determine what part of the Bunsen flame is the hottest and approximately what temperature can be achieved with a Bunsen flame.
Written Work
p. 96-98 # 57-62, 64-66, 74-77, 80, 82, 86, 87, 90, 92, 102
p. 99 # 2-14 even
Take a test on objectives and Bunsen burner lab. Bring calculator!!!!!…100pts
Supplemental Questions
This work will now be due two days before your next test to allow enough time evaluation and return
1. If for nothing more than to be amazed, visit http://www.usdebtclock.org/ . On the right-hand side of the page you will see some statistics that are static J (digits are not changing before your eyes). Convert the following statistics to scientific notation, rounding the coefficient to the tenth’s place and solve the problem, being mindful of significant figures.
Convert: US Population, US Actual Unemployed, US Work Force, and US Retirees & SSI.
Based on the above statistics, calculate the percentage of the US population that is comprised of youths that are unemployed by virtue of their age.
(for a refresher on how to handle significant figures in multiple operation calculations, watch the video in the “Data Analysis” power point located on dpav.wikispaces.com)
2. Blood glucose monitoring is an integral part of diabetes care. There are a large number of commercially available blood glucose monitors with varying degrees of accuracy in detecting blood glucose levels. Although most meters can detect levels with less than a 20% error, very few have the ability to meet the American Diabetes Association’s (ADA) desired maximum 5%percent error in detection.
A 75mg/dl standard sample of glucose was tested by three different monitors several times. Examine the data below and answer the questions that follow.
Monitor X / Monitor Y / Monitor Z79.2 / 71.5 / 67.5
57.4 / 78.0 / 66.9
58.7 / 76.7 / 67.8
82.3 / 74.6 / 67.4
a. Determine the average percent error for each of these monitors
(report your answers with the correct number of sig figs)
b. Do any of these monitors meet the percent error criteria established by the ADA? If so, which one?
c. Describe the accuracy and precision of each of these monitors. For accuracy, use an acceptable error of 15% for comparison.
3. Create an acronym that will help you remember the order of metric prefixes from giga- through pico-
4. Go to the website listed below and print out the “How Big are Things?” cube on card stock provide by Mrs. Pav, and assemble the cube. Write your name in ink on one side of the cube and show it to Mrs. Pav.
http://www.vendian.org/howbig/cube/UnstableURL/howbig_cube.pdf
Using your cube, determine what scale (which side of the cube) would be used to measure the following objects. Rewrite the measurement using that scale.
A carbon nanotube (Duh!) 0.00000030 meters ______
A speck of dust 0.0004 meters ______
The combined length of all the blood vessels in an average childs body 97000000 meters
______
5. Examine the scales below and answer the questions that follow.
a. Why do you think that the celcius scale is also known as the centigrade scale?
b. Knowing the equation for the conversion of Kelvin to celcius, propose an equation for the conversion of Fahrenheit to Rankine (F=?).
( Don’t worry, Fahrenheit and Rankine will not be on the testJ)
DV
6. Given the equation for density, draw a hypothetical line on each graph to demonstrate the relationship between the two variables on the axes. Below each graph, write whether the relation between the variables is direct or indirect (inverse).
DM
M
V
7. The density of bromine is 3.10g/ml. The graduated cylinder below contains a particular volume of liquid bromine. From this volume and the given density, calculate the mass of bromine in the sample. Convert this mass to centigrams.(be mindful of significant digits when recording your volume and significant figures in your calculations.
Volume = ______mL
8. Determine the density of the substance from the graph below.
Density =
Will this substance sink or
float when placed in water?
9. Examine the equations for the incomplete and complete combustion of methane in the Bunsen burner.
10g + 40g = 30g 10g + 40g = 50g
If you combine an equal number of grams of methane and oxygen in both equations, why is it that the total mass of the products for each equation are not equal.
Chemistry: Scientific Notation
Part A: Express each of the following in standard form (no exponents).
1. 5.2 x 105 5. 3.6 x 100
2. 9.65 x 10–4 6. 6.452 x 102
3. 8.5 x 10–2 7. 8.77 x 10–1
4. 2.71 x 108 8. 6.4 x 10–7
Part B: Express each of the following in scientific notation.
1. 78,000 5. 1.6
2. 0.00053 6. 0.0043
3. 250 7. 0.875
4. 2,687 8. 0.012654
Part C: Use the exponent function on your calculator (EE or EXP) to compute the following.
1. (6.0 x 1023) + (8.65 x 1024) 8. (7.03 x 1028) (3.2 x 10–20) (6.42 x 1035)
Answer without sigfigs: ______Answer without sigfigs: ______
Answer with sigfigs: ______Answer with sigfigs: ______
2. (6.02 x 1023) - (9.63 x 1021) 9. (– 6.02 x 1023) (–1.4 x 10–15)
6.54 x 10–6
Answer without sigfigs: ______Answer without sigfigs: ______
Answer with sigfigs: ______Answer with sigfigs: ______
3. 5.63 x 10–18 10. (6.02 x 1023) + (5.8 x 1024)
8.9 x 108 8.23 x 105
Answer without sigfigs: ______Answer without sigfigs: ______
Answer with sigfigs: ______Answer with sigfigs: ______
4. (– 4.1 x 10–4) (7.33 x 1012) 11. (3.1 x 10–12) – (4.48 x 10–13)
6.6 x 10–14
Answer without sigfigs: ______Answer without sigfigs: ______
Answer with sigfigs: ______Answer with sigfigs: ______
Practice Worksheet for Significant Figures
1. State the number of significant digits in each measurement.
1) 2800 m 2) 2.84 km 3) 0.005400 m
4) 0.003068 m 5) 4.6 x 105 m 6) 4.006 x 10-5 m
7) 75000. m 8) 75 m 9) 750 m
10) 75.00 m 11)75,000.0 m 12) 10. cm
2. Round the following numbers as indicated:
To four significant figures:
3.682417 21.869051 399.9523 0.0011298 45.4673
To two significant figures:
22.694 79.2588 0.03962 103.4125 41.46632
Measure the objects below. Record your measurements with the correct number of significant figures based on the instrument used to make the measurement.
(Remember: No Naked Numbers!!!!!)
METRIC CONVERSION WORKSHEET
Convert the following:
1. 36.52 g = ______mg
2. 14.72 kg = ______ng
3. 0 .0035 hm = ______dm
4. 0.134 Gm = ______km
5. 25 mm = ______cm
6. 2500 pL = ______L
7. 243L = ______daL
8. 45.23 mL = ______L
9. 0 .035 hL = ______cL
10. 27.32 mm = ______m
11. 0.000015 m = ______nm
12. 0 .023 cm3 = ______L
13. 0.00049 Mm = ______km
14. 0.025 kg = ______g
15. 15 g = ______hg
Density Problems
1. Mercury metal is poured into a graduated cylinder that holds exactly 22.5 mL. The mercury used to fill the cylinder weighs 306.0 g. From this information, calculate the density of mercury.
2. What is the weight of the ethanol that exactly fills a 200.0 mL container?
(The density of ethanol is 0.789 g/mL)
3. What volume of silver metal will weigh exactly 2500.0 g. The density of silver is 10.5 g/cm3
4. 4. A rectangular block of metal weighs 1896 g. The dimensions of the block are 8.4 cm by 5.5 cm by 4.6 cm.
a. From this data, calculate the density of the metal in g/mL?
b. Examine the table below and determine the identity of the metal.
5. Examine the picture below to evaluate the volume of a unknown piece of metal that has a mass of the 43.2 g.
a. From this data, calculate the density of the metal in g/mL?
b. Examine the table below and determine the identity of the metal.
Element / density(g /cm3)
Ti / 4.50
Cr / 7.20
Fe / 7.86
Co / 8.90
Ni / 8.90
Cu / 8.92
Zn / 7.14