Moles,Moles, Units,Units, andand ConversionConversion FactorsFactors PresentedPresented by:by: CenterCenter forfor TeachingTeaching andand LearningLearning andand DanielDaniel FoxFox WhyWhy dodo wewe measure?measure? • standardize •compare • quantify ExamplesExamples ofof measurementmeasurement • Speed- 100 MPH • Cooking- 4 cups flour • Building- 8 foot walls • Weight- lbs, g, kg, etc. • Money- dollars, euros, yen • Atoms- (??!!) EnglishEnglish MeasurementMeasurement SystemSystem • Length: • 12 inches (in) = 1 foot (ft) 3 feet = 1 yard (yd) 5280 feet = 1 mile (mi) • Capacity: • 3 teaspoons (tsp) = 1 tablespoon (tbsp) 16 tbsp = 1 cup (c) 8 ounces (oz) = 1 c 2 c = 1 pint (pt) 2 pt = 1 quart (qt) 4 qt = 1 gallon (gal) • Weight: • 16 ounces (oz) = 1 pound (lb) 2000 lb = 1 ton http://regentsprep.org/Regents/math/meteng/LesEng.htm MetricMetric SystemSystem ofof MeasurementMeasurement • Length - meters • Volume- Liters •Mass -grams • Time - seconds EnglishEnglish--MetricMetric ConversionsConversions http://www.its.dot.gov/transit_dev/BusSignage/images/conversionFactors.gif ScientificScientific NotationNotation 1,540,000,000,000 = 1.54 X 1012 0.00000000000154 = 1.54 X 10-12 Write these in scientific notation: 65,800,000 = 6.58 X 107 0.125 = 1.25 X 10-1 MetricMetric toto metricmetric conversionsconversions 9 10 106 103 100 10-1 10-2 10-3 10-6 10-9 Giga-(G) Mega-(M) kilo-(k) m deci-(d) centi-(c) milli-(m) micro-(µ) nano-(n) g Larger Measurements L Smaller Measurements s TheThe molmol • Avagadro’s Number 6.02 X 1023= 1 mol • Used as a ratio to compare different atomic elements MetricMetric toto MolesMoles • Write this: mass mols molar mass MolesMoles toto ## AtomsAtoms • Write this: #Atoms Avagadro’s mols Number 6.02 X 1023 molsmols ExampleExample • How many mols of are in 5g of carbon? 5g carbon = 0.417 mols of carbon 12 g/mol • How many moles of oxygen are in 12 g of CO2? • 12g CO2 X 2 atoms O =~0.55mols 44 g/mol 1 molecule CO2 #Atoms#Atoms exampleexample • How many atoms of Cl are in 0.43 mols of NaCl? 0.43mols (6.02 X 1023) = 2.59 X1023atoms • How many atoms of Na are in 3g of NaCl? 3g NaCl (6.02 X 1023) = 3.11 X 1023atoms 58 g/mol MolarityMolarity (M)(M) • Represents concentration of moles in a solution • Measured in moles/Liter •Ex: • A 1 Molar solution of NaCl: 1 mol NaCl 1 L solution ApplicationsApplications • Moles and molarity are used to: – Determine amount of substance needed – Calculate limiting reactants – Compare different elements and compounds on a standard scale ApplicationApplication questionquestion #1#1 • How many grams of NaCl are required to make 500mL of a 2.0M solution? 2.0 moles/liter (0.5L)= 1mol NaCl 1mol NaCl(58 g/mol) = 58 g NaCl ApplicationApplication questionquestion #2#2 • What is the molarity of 4g CaCl2 dissolved into 800mL of solution? 4g CaCl2 = .036mols CaCl2 110 g/mol .036mols= 0.045M solution 0.8L ApplicationApplication questionquestion #3#3 • How many mols of HCl are required to make 600mL of a 1.5M solution? 1.5mol/liter (0.6L) = 0.9 mols Happy Halloween! .