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Name:___________________________Period:__________________________Chemistry Unit 10 – Scientific MeasurementChemistry Daily JournalToday’s DateWhat do I need to accomplish today?What do I need to finish up at home?ObjectiveLearning OpportunitiesSuggested Due DateDate Completed9.1 Know how to write numbers and do calculations in scientific notationRead p. 62 – 71 and use the Math Handbook p. 69, 3 and 4, p. 70, 5 and 6, p. 71, 7 and 8, 9-10 pg. 72Podcast 2.1 Scientific NotationScientific Notation Practice02/179.2 Describe and apply accuracy, precision, and errorPodcast 2.2 Accuracy, Precision, and ErrorShooting Baskets Demo78-80 pg. 97Accuracy, Precision, and Percent Error Practice Problems02/199.3 Know how measurements’ uncertainties and significant figures apply to calculationsPodcast 2.3 Sig-FigsSig-Fig LabSignificant Figures Practice Problems02/199.4 Know the components for the metric system and how to convert from one metric prefix to anotherPodcast 2.4 Metric Mania18-24 pg. 79Mega Metric ManiaVolume of a Tennis Ball02/209.5 Be able to perform dimensional analysis using T-tablesPodcast 2.7 T-Tables38-45 pg. 87T-table Review and PracticeUnit Conversions02/239.6 Know how to calculate and describe density and specific gravityPodcast 2.6 Density and Specific Gravity50-56 pg. 93Coke vs Diet Coke DemoDensity Cubes Lab02/24Unit 9 Test Unit 9 Test – Scientific Measurement02/25 – 02/26Podcast 2.1 Scientific Notation Scientific Measurement: Using and Expressing MeasurementsMeasurements in chemistry often involve _____________ ______________ or ______________ ______________ numbersEXAMPLE. 2 grams of Hydrogen = 602,000,000,000,000,000,000,000 hydrogen atoms. Scientists use “____________________________ ____________________________” to write numbers in Exponential form Notation is based on powers of ______________ 10 = 101 100 = 1021000 = 10,000 = 100, 000 = Writing Numbers with Scientific Notation Move or add a decimal point so that only ______________ digit is in front of the decimal.Write ______________Count the number of decimal places you moved and write that number as ______________. Look which way you moved the decimalLeft = ______________ superscript or b. Right = ______________ superscriptLeft ______________ Right ______________Put the following numbers into or take them out of Scientific Notation:1) 134000002) 0.0007243) 5.903 x 10-8 4) 6.20 x 103 Calculations with Numbers in Scientific NotationAddition: Change exponents so they match EX. 1.03 x 103 + 2.10 x 102 Answer = ____________Subtraction: Change exponents so they matchEX. 1.03 x 103 - 2.10 x 102 Answer = _____________Multiplication: Multiply numbers and add exponents EX. 1.03 x 103 x 2.10 x 102 Answer = ______________Division: Divide numbers and subtract exponentsEX. 1.03 x 103 / 2.10 x 102 Answer = ______________Name: ________________________Per: ____ Date: ________________Scientific Notation PracticeConvert the following numbers to Standard Scientific Notation.0.0023_____________5) 1374000000_____________471000_____________6) 2515000_____________0.0124_____________7) 0.0000010032_____________0.000000000004_____________8) 201400000000000_____________Convert the following from Standard Scientific Notation to numerical form.1.37 x 107 ___________________12) 4.320 x 106 ___________________2.01 x 10-4 ___________________13) 3.002 x 10-7 ___________________7.90 x 10-13 ___________________14) 4.98 x 101 ___________________Complete the following calculations. DO NOT use a calculator. SHOW ALL YOUR WORK!!4.35x10-7 + 1.002x10-8 _______________________7.002x105 + 1.3x103_______________________2.9 x 106 1.2x10-3_______________________9.3 x10-13 ÷ 3.1x104_______________________1.002x102 – 7.10x103_______________________8.00 x107 1.11x10-5_______________________4.21 x1012 ÷ 1.00 x10-4_______________________3.0 x1032 – 4.51 x1029_______________________Podcast 2.2: Accuracy, Precision, and Error Uncertainties in Measurement _____________ – the closeness of a measurement to the true value of what is being measured._____________ – is a measure of how close a series of measurements are to one another. How do we measure Accuracy?By determining _______________measured value – correct value ____________________________ value – ____________________________ valueError = “______________ ______________” – “______________ ______________ ______________”Percent Error : How critical is the error?Percent error = Ex. Experimental = 1.24 g Accepted = 1.30 g Percent Error = Causes of Error Four types of Errors____________________________ error – error that deals with ________________ of instrument__________ error – error that deals with error in your human _________________________ to record observationsEnvironmental error – occurs when uncontrolled _________________________ conditions affect the _________________________ error – introduced from abnormal chemical behavior. Calculator Lesson: All calculators are NOT created equalGraphing calculators follow the _______________, so the use of parentheses is VERY importantSimpler calculators do the operations as you put them in Scientific Notation and your calculatorDepending on the calculator, the exponential key may be labeled “EE” “EXP” or “EEX” or you may not have one…bummerExample: 4.56×108 It’ll show up as either 4.568 or 4.56E8The ×10 is assumed so it’s not shownExample: What is 2.43 x 1023 x 7.30?Enter it as 2.43 EE 23 × 7.30Answer = __________________Optional: View “Podcast Scientific Notation w Calculator” Uncertainty in Measurements LabComplete the following with a partner. Go to each station and perform the measurements and answer the questions. Include units for each measurement!Station #1 – Temperature (?C)Using the digital thermometer, record the room temperature (in Celsius…ALWAYS!) _________What is the uncertainty digit in your measurement?Using the glass thermometer, record the temperature of the water in the beaker. ____________How many certain digits are in your measurement?Using the infrared temperature detector, record the temperature of the water in the beaker. ___________Why is there a difference? Which temperature do you think is more accurate?Station #2 – Mass (g)Using the digital scale, record the mass of object #1 (in grams…ALWAYS) ____________What is the uncertainty digit in your measurement?Using the three-beam balance, record the mass of object #2. _____________How many certain digits are in your measurement?Using the analytical balance, record the mass of either object. _____________How many digits are in this measurement? What does this mean for the accuracy and precision of your measurement? Station #3 – Volume (mL)Record the volume of water in the beaker (as accurately as your instrument will allow). Record the volume of water in the 100 mL graduated cylinder. ___________Record the volume of water in the 10 mL graduated cylinder. ____________Draw up 6.80 mL of water into the pipette. Record the measured volume. __________Which of the three instruments you used to record volume will allow you to have the most accurate measurement? Explain why.Station #4 – Length (cm)With the ruler, measure the dimensions of an index card to the precision of two decimal places. (length and width) Calculate the AREA of the index card.With the meter stick, measure the dimensions of the chemistry textbook to the precision of two decimal places. (length, width, and depth) Calculate the VOLUME of the textbook.Station #5 - TimeUsing the stop-watch, determine how accurately you can record time (ie, minutes, seconds, tenth of a second, etc). Explain pare the accuracy of the stopwatch to a timer on a cell phone, ipod, or ipad.Using the classroom clock, determine how accurately you can record time. Explain why.Additional Questions (review your notes if you’re not sure)Why is it important to include the right number of digits in a measurement?What determines the uncertainty of a measurement?Podcast 2.3: Significant Figures “Sig-Figs” Measurement UncertaintyMeasurements in science needs to be _____________ and therefore hopefully ______________Uncertainty on measurements are based upon the ___________________________ used4181475224155Made up of a number of digits that are ________________, and one additional digit which represents an ________________________________Example: Use a ruler to measure the length of the metal rod. The ___ and____ are the certain numbersThe _____ in the hundredth place is the uncertainty digit (based upon ruler provided)Length of rod ____________Significant Figures: ______________ digits in a MEASUREMENTExact numbers are counted, have unlimited significant figures_______ _______ except zero are significant.Some zeros are, some aren’t…Which Zeroes Count?______________ other sig figsNOT _____________ the first numberAfter the last number counts if and only if…-- it is after the _________________ – or – the decimal point is written in3200 ___ sig figs3200. ___ sig figs320.0___ sig figsHow many sig figs do the following numbers have? 1.032-0.00768001.302.4610.026800.0 Doing the Math For multiplication and division, your answer can only have as many sig-figs as the LEAST number of sig-figs in the problemEx: 1.31 x 2.2 = ______________For addition and subtraction, the number with the least number of decimal places is used. Ex. 1.31 + 2. 2 = Try These: 2.36 + 1.7 + 3.284 1.89 x 2.03 x 3.277 8.2 / 3.74 Please report your results with the appropriate number of significant figures. Thanks! 2.090 x 1.23 x 1.912.036 – 3.42 – 2.0671.096 + 7.09 + 5.213.040 / 3.23Significant Figures Practice ProblemsWrite the correct number of significant figures for each:.023 _____6) 6.00 x 106_____4000 _____7) 0.0808 _____1.200 x 10-7_____8) 0.0000100 _____100 _____9) 1.500 _____300.10 _____10) 2343.0_____State the number of significant digits that must be reported in the answers for the following calculations..1 × 2.4_____7. 30 - 0.5_____7.80 + 5.5_____8. 0.845 ÷ 0.015_____13.04 - 0.56_____9. 6.004 × 4.00_____20 ÷ 7.36_____10. 2.0 + 3.0 + 0.020_____24.3 + 0.41_____11. 1400 ÷ 20.6_____0.019 × 8.15_____12. 30.03 - 2.110 - 0.145_____Complete the following calculations and give the answer to the proper number of significant digits. SHOW ALL YOUR WORK!!!2.36 + 1.7 + 3.284 =______________3. 1.89 × 2.03 × 3.277 =______________15.8 – 3.02 – 2.937 = ______________4. 8.2 ÷3.74 =______________Accuracy and Precision/Percent Error Practice ProblemsFor each of the following situations FIND THE PERCENT ERROR involved. Be careful in determining the true vs. observed value. SHOW ALL YOUR WORK!!!Samantha S. Sloppiness measured the volume of her soda before she drank it for her midmorning snack. She measured the volume of the 12 oz. bottle to be 14 oz.Clyde Clumsy was directed to weigh a 500 g mass on the balance. After diligently goofing off for ten minutes, he quickly weighed the object and reported 458 g. Willomina Witty was assigned to determine the density of a sample of nickel metal. When she finished, she reported the density of nickel as 5.59 g/ml. However, Miraculous knew the density of nickel was 6.44 g/ml. Podcast 2.4 – SI and the Metric System (notes on Mega Metric Mania)Podcast 2.5 – Measuring Temperature Heat and Temperature ____________– the energy an object has due to the motion of it’s particles____________ – the average kinetic energy of all particles in an objectMeasures transfer of heatMovement of Heat Heat always moves from ________ to ________Objects tend to ________________ with an increase in temperature and contract with decreasing temperature. Measuring Temperature _________________ – the zero point on the Kelvin scale which is equal to -273 C. At this point all atomic motion theoretically stops. ______________ of Water – 100 oC or 212 oF ______________ of Water – 0 oC or 32 oF Converting Temperature Fahrenheit, Celsius, and Kelvin are all describing the same height of mercury on a thermometer, just using a different scaleF = C = K = *Note: Kelvin is based on absolute zero, so it does not use “degrees of change”, don’t use a ” o ” with the unit KExample Problems Convert 298 K to oC 2343150149225Convert 37 C to Kelvin280987521463000Convert 72 oF to Kelvin3333750129540001st change to oC 2nd change to K 523430578740000Convert 74 Kelvin to oF 2676525117475001st change to oC 2nd change to oF Phase Change Diagram Mega Metric ManiaNotes4417561148590To convert to a smaller unit, move decimal point to the right or multiply.00To convert to a smaller unit, move decimal point to the right or multiply.-112395-555625Basic Unit00Basic Unit566420139700To convert to a larger unit, move decimal point to the left or multiply.00To convert to a larger unit, move decimal point to the left or multiply.Different Types of Basic Units:Temperature:Other Useful Conversion Information:K =1 inch = _____________ cm1 mile = ________________ km?C =1 lb. = _______________ g1 oz = _______________ gAbsolute zero – 1 gallon = ____________ L1 oz = _______________ mL1 mL = _____________ cm3 1 hour = ________ min = ________ sec?F =?C =Try these conversions, using the ladder method.1000 milligrams = _______ grams 1 liter = _______ milliliters783 dekagrams = _________ megagrams0.736 centiliters = ________ nanoliters 14 kilometers = _______ meters890,036 picometers = _________ meters109 grams = _______ kilograms 250 meters = _______ kilometers5.6 gigawatts = ________ wattsCome up with your own pneumatic device to help you remember the order of the SI prefixes:GMKHDBDCMNPMega Metric ManiaConversion ChallengeWrite the correct abbreviation for each metric unit.1) _____ Kilogram 2) _____ Milliliter 3) _____ Kilometer 4) _____ Meter 5) _____ Millimeter 6) _____ Centimeter 7) _____ Gram 8) _____ Liter 9) _____ Milligram 10) _____ Picogram11) _____ Megameter 12) _____ Microliter13) _____ Gigagram14) _____ Nanogram13) _____ DecimeterTry these conversions, using the ladder method.1) 2000 milligrams = _______ grams 2) 104 kilometers = _______ meters3) 480 centimeters = _____ meters4) 5.6 kilograms = _____ grams5) 8 millimeters = _____ centimeters6) 5 liters = _______ milliliters7) 46 hectograms = ________Gigagrams8) 12400 picoliters = ________ dekaliters9) 45 millimeters = ________ nanometer10) 67 megagrams = _________ gramsNow do the conversions using the abbreviations.11) 198 g = _______ kg12) 75 mL = _______ L13) 50 cm = _______ m14) 5.6 m = _______ cm15) 16 cm = _______ mm16) 2500 m = _______ km17) 65 g = _______ mg18) 6.3 cm = _______ mm19) 120 mg = _______ g20) 3487 ?L = ______ L21) 0.086 Gg = _______ cg22) 9800 ρm = _______ nm23) 9123 hg = ______ Mg24) 0.0034 daL = _______mL25) 8731 dm = _______ kmSome “Other Conversion” Problems.26) 68?C = __________ K27) 376 K = __________?C28) 0?C = ___________K29) 0 K = __________?C30) 100?C = __________ K31) 80?F = ___________?C32) 4.3 mL = ________ cm333) 3 hours = ________ sec34) 10 inches = ________ cmNow some word problems… (bum, bum, bummmmm)35) How many liters are in 246 centiliters? ___________________36) How many millimeters are in 0.237 meters? ____________________38) An Olympic distance triathlon consists of a 1.5 kilometer swim, 40 kilometer bike ride, and a 10 kilometer run. How many km does an athlete cover over the course of an entire triathlon? ____________________ How many meters? _______________________39) How many seconds are in one awesome Chemistry class period (92 minutes)? __________40) The altitude of Mt. Everest is 8,850 meters. How tall is Mt. Everest in feet? (1 mile = 5280 ft)___________________________Volume of a Tennis Ball Mini-LabPurpose: How can significant figures be used to determine the volume of a tennis ball?Hypothesis:Materials: Procedure:Obtain the necessary materials.Determine the Circumference of your tennis ball. (Remember: Circumference = 2πr)Using your value for circumference, which has been read to the proper degree of accuracy with the meter stick, calculate a value for the radius of your tennis ball.Using the value obtained for the radius, calculate the Volume of your tennis ball. (Remember: Volume of a Sphere = (4/3)πr3)Using the Actual value for the volume of the tennis ball, calculate a value for Error.Using your value for error, calculate a Percent Error.Data and Data Analysis: (SHOW ALL CALCULATIONS)Circumference of the tennis ball:________________________ cmRadius of the tennis ball:________________________ cmVolume of the tennis ball: ________________________ cm3 Volume of the tennis ball:________________________ m3 Error:________________________ cm3 Percent Error:________________________ %Questions:What types of Error contributed to your experiment?How many significant figures should your value of Volume have? How do you know this?Error Analysis:If the string used to measure the tennis ball was stretched during the measurement of the circumference, how would this error influence the calculation of the tennis ball volume (too high or too low)?Suppose that one student used a regulation tennis ball, while their lab partner used a dog-toy tennis ball. Describe the potential error in this situation.One of the newer tennis balls had a fuzzier surface than the older, more worn tennis ball. What kind of error occurs when two students use these two different tennis balls in their measurements and how does it influence the calculation of the volume?Podcast 2.7: Dimensional Analysis and T-Tables Dimensional Analysis Using _________ to help solve problemsA ______________________________ can be used to convert between different units. Conversion factors are reversible so that you can obtain the result you need.T-Table and Conversions In chemistry we use a T-table to help us convert between different units. Example 1: Convert 157 cs to sExample 2: 8.25 x 102 cg to ng Example 3: 0.44 mL/min to μL/s Example 4: The radius of a potassium atom is 0.227 nm. Express this radius in the unit centimeters.Please use T-Tables to convert the following units. Example 5: The diameter of Earth is 1.3x104 km. What is the diameter expressed in decimeters?Example 6: Light travels at a speed of 3.00 × 1010cm/s. What is the speed of light in kilometers/hour? Using T-tables to Solve Density Problems: Use density as a conversion factor to change mass to volume or volume to massg/mL or mL/gExample 7: Convert 6 g to mL if the density of the substance is 12 g/mLT-Table Review and PracticeWrite the given number and unit. Set up a conversion factor (fraction used to convert one unit to another).Place the given unit as denominator of conversion factor.Place desired unit as numerator.Place a “1” in front of the larger unit.Determine the number of smaller units needed to make “1” of the larger unit.Go to base units first (meter, Liter, gram).Cancel units. Solve the problem. A vertical line means multiply (x), whereas a horizontal line means divide, (÷).Example 1: 55 mm = _____ mExample 2: 88 km = _____m55 mm|1 m1000 m=0.055 m88 km|1000 m1 km=88,000 mExample 3: 7000 cm = _____ hmExample 4: 8 daL = _____ dL7000 cm1 m100 cm1 hm100 hm=0.7 hm 8 daL10 L1 daL10 dL1 L=800 dLExample 1: 55 mm = _____ mExample 2: 88 km = _____m55 mm|1 m1000 m=0.055 m88 km|1000 m1 km=88,000 mExample 3: 7000 cm = _____ hmExample 4: 8 daL = _____ dL7000 cm1 m100 cm1 hm100 hm=0.7 hm 8 daL10 L1 daL10 dL1 L=800 dLConvert 3 cm to kmConvert 8 hL to nLConvert 9 mL to MLConvert 1 kg to dg** Special Challenge: Convert 6cg/daL to g/mLUnit Conversions Convert 20.33 cm to m20.33 cm1 m= 20.33 *1 m= 20.33 x 10-2 m102 cm 102Convert 12.06 L to cL12.06 L102 cL= 12.06 *102 cL= 1,206 cL1 L 1 LConvert 32.27 kg to g32.27 kg103 g= 32.27 *103 g= 1 kg 1 kgConvert 13.09 m to cm13.09 m102 cm= 13.09 *102 cm= 1 m 1 mConvert 3.47 mm to m3.47 mm1 m= 103 mm Convert 33.81 kg to g33.81 kg103 g= 1 kg Convert 9.92 kL to L9.92 kL= kL Convert 2.61 g to mg2.61 g= g Convert 24.37 g to mgConvert 28.77 L to cLConvert 22.04 mL to LConvert 9.42 L to mLConvert 20.03 cm3 to mLConvert 23.28 L to mLConvert 9.72 mL to LConvert 1.47 kg /m3 to g/cm31.47 kg103 g1 m3=1 m31kg (100 cm)3Convert 7.18 mL/min to cL/sec7.18 mL L cL1 min =1 min L ______ secConvert 33.21 cg to mgConvert 30.62 mg to cgConvert 16.43 mg to cgPodcast 2.6: Density and Specific Gravity Density – is the ratio of the mass of an object to its volume. Formula for DensityUnits are given as _______ or _______Example1: A copper rod has a mass of 0.52g. The volume was determined by water displacement to be 0.0581 mL. What is the density?Example 2: A 1.60-L sample of tin (II) fluoride has a mass of 2.59 kg. What is the density of this substance in g/cm3?Example 3: What is the volume of 7.4 x 103 mg of copper if the density is 8.92 g/cm3 ?Example 4: A beach ball with a volume of 21.8 cm3 has a mass of 16.1 g. Would this ball sink or float in water?Specific Gravity: A comparison of the density of a substance with the density of a reference substance that is at the same temperature.Reference Substance = (usually) ___________ at 4o CFormula of Specific GravitySpecific Gravity is the only _____________ quantity.Example: A chunk of granite weighing 31.2 grams displaces 11.8 cm3 of water. What is the specific gravity of this rock?Density Mini-LabRead section 3.4 (pages 89-93) in your textbook on density and answer the following questions BEFORE starting the lab.Connecting to Your WorldWhat determines whether and object floats or sinks in water?What is the ratio for water at 4?C?Determining DensityWhich is heavier, a pound of lead or a pound of feathers? Make sure you give the correct answer and EXPLAIN WHY!Define density.What is the equation (yellow box) for density?Density can be measured in g/mL AND g/cm3. Explain how this can be (hint: Mega Metric Mania Chart)Key Point: What determines the density of a substance?Is density a physical or chemical property (the answer is not in this section of the book…look back at your notes from last section)?Density and TemperatureHow does a change in temperature affect most objects density?How is water different from most substances in regard to density? What should ice do?Density Mini-Lab ProcedureMeasure the MASS of each cube using the scale. Record in your data table accurately. Include units and the appropriate number of significant figuresMeasure the volume of each density cube. Fill the water displacement container to the top of the spout (just so a little water runs out). Let it sit until no more water comes out.Place a graduated cylinder under the spout (somebody will have to be holding it at an angle).Put the cube into the container and catch the water with the graduated cylinder.Measure the volume of the cube by recording the volume of the water that was displaced. Watch those uncertainty values. Make sure you have enough digits!Record in your data table accurately. Include units.Calculate the density for each cube.Show your calculations IN YOUR DATA TABLE (plug the numbers into the equation).Double check you have the correct number of significant figures.Record density for each cube in your data table. Include units.Get the actual density value for each metal and CALCULATE YOUR PERCENT ERROR.Show your calculations (plug the numbers into the equation).Double check you have the correct number of significant figures.DATA TABLEMassVolumeWorkDensityIdentity of MetalActual ValuePercent ErrorPractice ProblemsSolve the following problems in the space provided. SHOW YOUR WORK!A rock has a mass of 127 g and displaces 32.1 mL of water. What is the density of the rock?A 1.00-L sample of carbon tetrachloride has a mass of 1.58 kg. What is the density of this substance in g/cm3?A bar of silver has a mass of 68.0g and a volume of 6.48 cm3. What is the density of silver? ................
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