What is the same about these objects? Density

What is the same about these objects? Answer: These bottles all have the same volume. Volume= Amount of Space and object takes up

What is different about these objects?

Answer: They contain different samples of matter (cotton balls, water, iron filings, and air.) Mass= Amount of Matter in an object

What is Density? Density is the amount of matter in a given space Which of the bottles is the MOST DENSE?

Example Bobby Bobby takes a trip to Florida. Compare his suitcase before his flight and after his flight.

Bobby’s Suitcase Imagine these boxes represent Bobby’s suitcase. Which would represent Bobby’s suitcase before his flight? Which would represent his suitcase after his flight? Which is More Dense?

Which one is more dense? Demonstration: People in a square How about this: Which square is more dense? AB

Formula for Density We use the formula: Density = mass/Volume OR Density = mass Volume

Liquid Layers Which layer has the highest density? Which layer has the lowest density? Imagine that the liquids have the following densities:  10g/cm 3.3g/cm 3.  6g/cm 3.5g/cm 3. Which number would go with which layer?

4. The DENSITY formula can be remembered using this trick: Inside the T-Triangle add the three letters from the Density formula. D = m/V Think: but put a D in place of the T. m DV

6. Let’s solve a problem using the DENSITY T-Triangle! Example #1. What is the density of an object with a mass of 50 g and a volume of 100 cm 3 ? What is the formula for Density? m DV

6. Here’s how you solve the problem. Example #1. What is the density of an object with a mass of 50 g and a volume of 100 cm 3 ? FormulaSubstitute Solve (1) D = m/V (2) D = 50 g / 100 cm 3 (3) D = 0.5 g/cm 3

7. Let’s solve another problem using the DENSITY T-Triangle! Example #2. What is the mass of an object with a density of 1.2 g/mL and a volume of 0.3 mL? What is the formula for mass? m DV

7. Here’s how you solve the problem. Example #2. What is the mass of an object with a density of 1.2 g/mL and a volume of 0.3 mL? FormulaSubstitute Solve (1) m = DV (2) m = 1.2 g/mL X 0.3 mL (3) m = 0.36 g Notice: The like terms (mL) were cancelled so only “g” was left for the answer!

8. Let’s solve another problem using the DENSITY T-Triangle! Example #3. What is the volume of an object with a density of 3 g/cm 3 and a mass of 30 g? What is the formula for volume? m DV

8. Here’s how you solve the problem. Example #3. What is the volume of an object with a density of 3 g/cm 3 and a mass of 30 g? FormulaSubstitute Solve (1) V = m/D (2) V = 30 g X 3 g/cm 3 (3) V = 10 cm 3 Notice: The like terms (g) were cancelled so only “cm 3 ” was left for the answer!

10. Solve these problems. Example #4: What is the mass of an object with a density of 5 g/cm3 and a volume of 15 mL? Example #5: What is the density of an object with a mass of 300 g and a volume of 30 mL? Example #6: What is the volume of an object with a mass of 25 g and a density of 5 g/mL?