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Warm-up (IB):. Do the following metric conversions showing dimensional analysis 62.262 km to m 44.721 mm to km 2.15 cm to mm. Scientific Notation. Write out 600 sextillion out on your paper (hint: that is a 600 with 21 zeros behind it. 600,000,000,000,000,000,000,000
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Warm-up (IB): • Do the following metric conversions showing dimensional analysis • 62.262 km to m • 44.721 mm to km • 2.15 cm to mm
Scientific Notation • Write out 600 sextillion out on your paper (hint: that is a 600 with 21 zeros behind it. • 600,000,000,000,000,000,000,000 • Would you want to write that number out 20 times on your paper when doing calculations? This number is a common number in chemistry.
Scientific Notation • There are 2 reasons why we have scientific notation • 1. It is easier to write very large and vary small numbers. • 2. It allows us to convey numbers easily with the correct number of sig figs. • Format: Numbers are written as a product of a number between 1 and 10, times the number 10 raised to a power. • Ex. 6.02x1023 or 6.02x10^23
Scientific notation • A negative exponent for a number means that number is less than 1. • A positive exponent for a number means that number is greater than 1.
Scientific Notation • Converting decimal to Scientific notation • RNLP- “Registered Nurses Love Patients”, Right for negative and left for positive • 1090000 • 1.09x10^6 • 0.000462 • 4.62x10^-4 • Converting Scientific notation to decimal • Use opposite rules for RNLP • 5.92x10^3 • 5920 • 8.2x10^-5 • 0.000082
Practice • Convert to Scientific notation • 23600 a.) 2.36x10^-2 b.) 2.36x10^-4 c.) 2.36x10^2 d.) 2.36x10^4 • 0.01054 a.) 1.054x10^-2 b.) 1.054x10^-4 c.) 1.054x10^2 d.) 1.054x10^4 • Convert to decimal notation • 8.15x10^4 a.) 0.000815 b.) 81500 • 6.046x10^-2 a.) 0.06046 b.) 604.6
Extra Practice Convert the following to Scientific Notation • 4230100 0.00000032 400 Convert the following to Decimal Notation • 6.02x10^4 5.21x10^-3 8x10^-6 4.2301x10^6 3.2x10^-7 4x10^2 6020 0.00521 0.000008
Warm-up: • Solve the following problems. • 3 x 4 4 3 • 6 x 1 x 8 8 6 2 • cm x in x ft = cm in • g x mol x atoms = g mol
Dimensional Analysis • Also called unit conversion • Purpose: convert units of one thing to the next • Ex. Convert feet to inches, kilometers to meters, etc. • How it works • Dimensional analysis is finding a conversion factor which equals one and using that to switch units
Examples • Convert 2 feet to inches. • First need to know how many inches in a foot. • 1 foot = 12 inches • 2 ft x 12in = 1ft • Convert 45 cm to meters • First need to know how many cm in a meter • 1 meter = 100 cm • 45cm x 1m = 100cm
1000 m = 1 km • 100 cm = 1 m length problems • 1000 mm = 1 m • 1000 L = 1 kL • 100 cL = 1 L volume problems • 1000 mL = 1 L • 1000 g = 1 kg • 100 cg = 1 g mass problems • 1000 mg = 1 g
Examples • Convert your age in years to seconds. • First need to know the path you’re going to take. • We know how many days are in a year (365d = 1yr) • We know how many hours are in a day (24hr = 1 day) • We know how many minutes are in an hour (60min = 1 hr) • We know how many seconds are in a min (60s = 1min) • Now put it together starting with what you know. • 16 yrs x xxx = 365d 24hr 60min 60s IDC 1yr 1d 1hr 1min
Dimensional Analysis Examples • 15.2 days into hours • 24.0 hours = 1 day • A) 1 day B) 24 hrs 24 hrs 1 day
Dimensional Analysis Examples • 30.0 centimeters into inches • 1 inch = 2.54 centimeters • A) 1 in. B) 2.54 cm 2.54 cm 1 in. • 16 meters/second into miles/hour • 1 meter/second = 3.60 km/h • 1 km/h = 0.621 mi/h • A) 1 m/s B) 3.6 km/h 3.6 km/h 1 m/s • A) 1 km/h B) 0.621 mi/h 0.621 mi/h 1 km/h
Dimensional Analysis Examples • 2.1 light years into feet • 1 light-year = 9.46 x 1015 meters • 1 foot = 0.31 meters • A) 1 lyr B) 9.46x10^15 m 9.46x10^15 m 1 lyr • A) 1 ft B) 0.31 m 0.31 m 1 ft
Dimensional Analysis Examples • 14.6 kilometers into inches • 1 km = 0.621 miles • 1 mile = 5280 feet • 1 foot = 12 inches • A) 1 km B) 0.621 miles 0.621 miles 1 km • A) 1 mile B) 5280 ft 5280 ft 1 mile • A) 1 ft B) 12 in. 12 in. 1 ft
Warm-up: • Without a calculator solve the following problems • 1312 x 1 x 1000 100 1 • 546 x 1 x 1 x 1 x 100 x 100 100 10 1000 1 1
2 types of measurement systems • English system • System is based off of the kings • The system used to change for every new king • Now the system is stable but is confusing to convert • Metric system • Developed to reduce the problems of conversion • System is used by the majority of the world • The whole system is based off of powers of 10
Metric System • The metric system is based on a base unit that corresponds to a certain kind of measurement • Length = meter (m) • Volume = Liter (L) • Weight (Mass) = gram (g) • Prefixes plus base units make up the metric system • Example: • Centi + meter = Centimeter • Kilo + liter = Kiloliter
Metric System • The three prefixes that we will use the most are: • kilo • centi • Milli • What you need to know is what those prefixes mean. • Kilo (k) = 1000 • Centi (c) = 1/100 • Milli (m) = 1/1000
Conversion cards FRONT, use reciprocal for back 1000g 1kg 1000L 1kL 1000m 1km 100cg 1g 100cL 1L 100cm 1m 1000mg 1g 1000mL 1L 1000mm 1m
Metric conversions • Lets start by doing a simple conversion. • Convert 2 kilometers into meters • We start with what we know • 2 km x • We now need to find a relationship between km to m. • We know that kilo = 1000. So a km = 1000m • We can use that as a conversion factor to solve • 2 km x 1000m = 1km
Metric conversions • Lets do a 2 step conversion. • Convert 1534 millimeters into kilometers • We start with what we know • 1534 mm x x • We now need to find a relationship between mm to km. • We know that milli = 1/1000. So a mm =1/1000m or 1000mm = 1m • We can then convert that meter into km by kilo = 1000. So a km = 1000m • We can then use the information as conversion factors • 1534 mm x 1m x 1km = 1000mm 1000m
40mL x 1 L = 0.04 L 1000mL • 40ml=____ L • 5000 L=____ kL • 8 g=____ kg • 12000 L=____ kL • 50 mg=____ g 5000 L x 1 kL = 5 kL 1000 L 8 g x 1 kg = 0.008 kg 1000 g 12000 L x 1 kL = 12 kL 1000 L 50mg x 1 g = 0.05 L 1000mg
4000 L x 1 kL = 4 kL 1000 L 400 cm x 1 m = 4 m 100cm • 4000 L=___ kL • 400 cm=___ m • 20 ml=___ kL • 7000 ml=___ L • 7 cm=___ mm 20 ml x 1 L x 1 kL = 0.00008 kL 1000 mL 1000 L 7000 L x 1 L = 7 L 1000 mL 7cm x 1 m x 1000mm = 70 mm 100cm 1m