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Page 24. Objective 09/17/12. SWBAT incorporate the skills and factors about mass to lab and investigation. . Jumpstart. If you were finding the mass of an elephant would you use kilograms or centigrams? Explain why. Outro.
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Page 24 Objective 09/17/12 SWBAT incorporate the skills and factors about mass to lab and investigation. Jumpstart If you were finding the mass of an elephant would you use kilograms or centigrams? Explain why. Outro Which unit of measurement would you use to measure the mass of: A penny? A grain of rice? A piece of chicken? A bus?
MASS INTERACTIVE NOTEBOOK PAGE 25
Mass • What is Mass? • The measure of how much matter something contains. More commonly, how much something weighs.
Mass • GramsGramsGramsGramsGramsGramsGrams • Triple Beam Balance • The base unit for mass measure in the metric system • The tool used to measure mass in lab
Mass • How much is a gram? How much is a gram? How much is a gram? How much is a gram? • How many pounds are in a kilogram? • One penny equals about 2 ½ grams • One kilogram equals about 2 ½ pounds
1 pound = 453.6 grams 1 ounce of gold = 28,349.5 milligrams 100 kilograms = 220 pounds English vs. Metric Units Which is larger? 1. 1 Pound or 100 Grams 2. 1 Kilogram or 1 Pound 3. 1 Ounce or 1000 Milligrams
Zeroing/Calibrating: Move “riders” to the left Check pointer on right side If lined up, fine If not lined up, calibrate using the adjusting knob on the left side Pointer go up, turn away from you Pointer go down, turn towards you Adding a load: Slowly and gently Reading mass: Start with heaviest rider Too light, move riders forward Too heavy, move riders backward Once balanced, add values from all three riders (nearest 1/10 gram) Page 3- Preparing & Using the TBB
Page 3- Reading a Triple Beam Balance • Parts of the 3-Beam Balance • Tray- Hold the load/objects to measure • Beams/ Riders- move to see the accurate number of grams • Adjustment Knob- To zero/calibrate the balance • Pointer- To indicate if the balance is calibrated
What would be the mass of the object measured in the picture? _______ + ______ + _______ = ________ g 216.5 g 165.3 g
What would be the mass of the object measured in the picture? _______ + ______ + _______ = ________ g 373.35 g 62.4 g
Page 3- Reading a Triple-Beam Balance • 132.5 g • 133.3 g • 34.5 g • 150.5 g • 104.3 g • 120.5 g
Page 4- Measuring Mass Lab • Materials needed: • Penny • Large paperclip • Rubber Stopper • Beaker • Water 150 mL 50 mL
Page 24 Objective 09/17/12 SWBAT incorporate the skills and factors about mass to lab and investigation. Jumpstart If you were finding the mass of an elephant would you use kilograms or centigrams? Explain why. Outro Which unit of measurement would you use to measure the mass of: A penny? A grain of rice? A piece of chicken? A bus?
Page 26 Objective 09/17/12 SWBAT incorporate the skills and factors about mass and volume to lab and investigation. Jumpstart • Which object has a greater mass? • Which object is more massive?
Density Interactive Notebook Page 27
Density • Density- mass per unit volume of an object; physical property used to identify and classify substances • gold vs. pyrite (fools gold) • salt water vs. fresh water • steel vs. aluminum • solid vs. liquid vs. gas
Density Mass m Volume v Density = = Mass m Density d Volume = = Mass = Density × Volume
Page 7- What is Density? Look at the two boxes below. Both boxes have the same volume. • If each red sphere has the same mass, which box would weigh more? Why? • The box on the left. • The box that has more spheres has more mass per unit of volume. This property of matter is called density.
Page 7: Density Principle #1: If you pack MORE mass into the SAME volume, it is MORE dense. • Draw a two squares, the same size. • Draw 6 small circles inside the 1st square (like a gumball machine) • Now, draw 12 small circles inside the 2nd square. More Dense!
Density Principle #2: If you pack the SAME mass into a SMALLER volume, it is MORE dense. • Draw a two squares, one large in size, one small in size. • Draw 6 small circles inside the 1st larger square (like a gumball machine) • Now, draw 6 small circles inside the 2nd, smaller square. More Dense!
More Dense! Density Principle #3: Just because something has more mass, does NOT mean it is more dense. More Mass!
Accelerated: Density Quick Check You have 3 metal samples. Which one will displace the greatest volume of water? 12 3 Discuss your choice with your table partner. 25 g Aluminum = 9.2 mL 2.70 g/mL 25 g Aluminum 2.70 g/mL 45 g of Gold 19.3 g/mL 75 g of Lead 11.3 g/mL Mass Density Volume =
Density Lab- Investigation OneDensity of a Regularly Shaped Object • Density Cube Choices: • Steel, brass, acrylic, wood (oak/pine/poplar), nylon, PVC • Choose 3 different cubes • Find the mass of the cubes • Measure the linear dimensions • Calculate the volume • Calculate the density
Density Lab- Investigation TwoDensity of Rectangular Solids • Obtain a plastic block from the teacher. Record the color of the sample. • Color of Block: __________ • Measure the dimensions (length, width, and height) of the block. Estimate all measurements to the correct decimal place and include units with each measurement. • Length: ___ Width: ___ Height: ___ • Calculate the volume of the block. Record the volume in the data table. Be sure to include the appropriate units. • Volume: __________ • Use the known density value and the volume calculated in question 3 to predict the mass of the plastic sample. • Predicted Mass of Block: __________ • When the mass of the plastic block has been calculated and a prediction made, bring the block to the teacher. • The teacher will measure the actual mass of the block using a laboratory balance. • Actual Mass Measurement: ______ • Determine the accuracy of the mass calculation by comparing the predicted (calculated mass) with the actual (measured) mass. Calculate the percent error of the mass calculation using the equation below: Percent Error = | Calculated Mass – Actual Mass | × 100 = Actual Mass
ACC Density Lab- Investigation ThreeThickness of Aluminum Foil • The density of Aluminum is 2.7 g/cm3 • How can you find the thickness of a piece of Aluminum foil? • What information do you need to calculate density? • What measurements should you make of your foil? Large roll of aluminium foil, with micrometer showing a thickness of 0.0005 in (0.013 mm)
ACC Density Lab- Investigation FourIndiana Jones • In the 1981 movie "Indiana Jones: Raiders of the Lost Ark," there is a scene where Indiana Jones switches a gold statue with a bag of sand. The gold statue is protected from theft by a triggering device. The switch must be made with a mass that is equal to the gold statue to avoid springing the trap and bringing disaster! • Useful Information: • The density of sand is 2.5 g/cm3 • The density of pure solid gold is 19.32 g/cm3 • The approximate volume of the gold statue is 1.25 L • Did Indiana Jones have a reasonable chance of exchanging the bag of sand for the gold statue?