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Warm-Up. List 1 exciting thing you did over the break. I will call on 3 volunteers to share their answer. Agenda. Review Rules & Procedures Review of Measurement & Units. Classroom Rules. Don’t talk while someone else is talking. Do not make fun of another student’s ideas.
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Warm-Up • List 1 exciting thing you did over the break. I will call on 3 volunteers to share their answer.
Agenda • Review Rules & Procedures • Review of Measurement & Units
Classroom Rules • Don’t talk while someone else is talking. • Do not make fun of another student’s ideas. • Be in your seat with paper and writing utensil on your desk. • Cell phones are to be off and stowed away in your backpack, locker, or purse.
Units • What is a Unit? Take a moment to write down what you think a unit is. • By Definition: “a quantity chosen as a standard in terms of which other quantities may be expressed.” • You don’t have to write this down • What does that even mean? • What key words stand out to you in that definition? • Quantity • Standard • Expressed
Units • Type of measurement, based on a standard system, that tells us the value of that number. • Ex: 1 meter; 1 second; 1 gram • Each unit identifies what that number represents. • Distance, time, mass • Without the unit, the number means nothing: 1 • 1 What?
Recall • Units are based on a standard system. • There are two main systems • English • Metric • In the US we use English, but in science we use the Metric System • We will spend the rest of today on the metric system. • NOTE: You will be expected to convert between English and Metric (we’ll get into that later).
The metric system The International System of Units and A Method of Problem Solving Called Dimensional Analysis
SI Prefixes Prefixes can be placed in front of the base units. These prefixes are used to represent quantities that are larger or smaller than the base units. These prefixes must be memorized. King Henry Doesn’t Usually Drink Chocolate Milk
How many meters are in each of the following? (hint: this is the “meaning” column) 1 Gm = ? m 1 Mm = ? m 1 km = ? m 1 hm = ? m 1 dam = ? m ? dm = 1 m ? cm = 1 m ? mm = 1 m ? m = 1 m ? nm = 1 m 1,000,000,000 m 1,000,000 m 1,000 m 100 m 10 m 10 dm 100 cm 1,000 mm 1,000,000 m 1,000,000,000 nm
Metric Unit of Length The meter (m) is the SI base unit of length. Prefixes are used to indicate distances longer and shorter than a meter. What name and symbol is given to each of the following units of length? • .000001 m • .001 m • .01 m • .1 m • 10 m • 1000 m Micrometer m Millimeter mm Centimeter cm Decimeter dm Decameter dam Kilometer km
Measuring Length • What tool do we use to measure length? • A Ruler • Remember – rulers usually have both English (inches) and Metric Units (cm) on them. • How do we know which one is metric?
1 2 3 4 5 Scientific Measurement: Length • When we measure something, we always estimate between the smallest marks.
Scientific Measurement • Scientist always understand that the last number in a measurement is actually an estimate. • The numbers represent cm, the smaller tick marks are mm. 1 2 3 4 5 4.55 cm
Metric Unit of Volume Volume: Is the space occupied by a sample of matter. The cubic meter (m3) is the SI derived unit for measuring volume. When chemists measure the volumes of liquids and gases, they often use a non-SI unit called the liter. The two units, _________________, are interchangeable. mL and cm3 Therefore: 1mL = 1 cm3
Measuring Volume LIQUIDS RECTANGULAR OBJECTS • What equipment we use to measure liquid volume? • Graduated cylinder • How do we measure liquid volume? • Meniscus • What equipment we use to measure liquid volume? • Ruler • How do we measure liquid volume? • Length*Width*Height
Measuring Volume of Liquid • Use a graduated cylinder meniscus http://chemistry.about.com/od/chemistry-test-questions/tp/Measurement-Test-Questions.htm http://www.uwplatt.edu/chemep/chem/chemscape/labdocs/catofp/measurea/volume/gradcyl/pic/00322409.jpg
Measuring Volume of Non-Rectangular Objects • Non-rectangular objects • Water displacement http://www.chemistryland.com/CHM130FieldLab/Lab1/Lab1.html
Metric Unit of Mass Mass: The quantity of matter an object contains. Weight: A measure of the pull by earth's gravity. Mass and weight are often confused. Mass is not affected by gravitational pull. Your weight on the moon would be less, but your mass on the moon would be the same. The _______________ is the SI base unit for measuring mass. Kilogram (kg)
Measuring Mass • What equipment do we use to measure mass? • Triple-Beam Balance 2 1 373.32g 3, 4 http://genchem.rutgers.edu/balance3b.html
Metric Unit of Temperature 273 K • Kelvin (K) • Absolute Zero = Zero K • Can never reach absolute zero • Kelvin can never be negative. • Unit conversions: Add/Subtract 273 • Kelvin to degrees Celsius: C = K -273 • Degrees Celsius to Kelvin: K = C + 273 • Kelvin is always bigger.
Measuring Temperature • What equipment do we use? • Thermometer • Usually in degrees Celsius or degrees Fahrenheit • Convert from Celsius to Kelvin
Independent Practice • Around the room are several stations. • Each station has a worksheet (there should be multiple copies of the SAME worksheet there). • Work with a partner to complete the worksheet. • You EACH need to turn in a piece of notebook paper with all of your answers on it. • Be sure to include your station number with your answers! • You will have 5 minutes at each station. USE YOUR TIME WISELY.
More Practice with Units! On the following slides are several questions referring to units. Use your table to answer the questions. This WILL be turned in.
Give the name and symbol for each of the following units: 1. A time that is 100 times as great as 1 second = 2. A length that is 1/1000 the length of 1 meter = 3. A mass that is 1000 times as great as 1 gram = 4. A mass that is 1/1,000,000 the mass of 1 gram = • Hectosecond (hs) • Millimeter (mm) • Kilogram (kg) • Microgram (g)
State the quantity that is measured by each of the following units: 5. centigram 6. millimeter 7. Kelvin 8. millisecond 5. Mass 6. Length 7. Temperature 8. Time
How large is: • 9. a kilogram, compared with a gram? • 10. a millimeter, compared with a meter? • 11. a centimeter, compared with a meter? • a nanogram, compared with a gram? • 13. a decameter, compared with a meter? • 1000 times larger • 1/1000 as large • 1/100 as large • 1/1,000,000,000 as large • 13. 10 times larger
Closure: Exit - Ticket • On the bottom of your paper answer the following questions: • What is the • Metric Base Unit for Length? • Metric Base Unit for Mass? • Metric Base Unit for Time? • How many meters are in a kilometer?