1. Quiz 9/30 1. 1000g = 1 ___ 2. 0.01L = 1 ___ 3. 0.23 m = 2.35 ___ 4. Find the density of a 2 cm 3 object weighing 1 gram. 5. Describe a procedure to find the volume of a cylinder. 1. 1000g = 1 kg 2. 100L = 1 cL 3. 0.23 m = 2.35 dm 4. 4. 5. 5. D = m/V D = (1.0g/2cm 3 ) There are two ways to measure volume, 1) measure radius and length, then calculate area of a circle,… the volume π r 2. ht 2. Or, measure the volume of water in a graduated cylinder then the new volume with the Cylinder.

2. Density: how much mass per unit volume? Volume is measured in three dimensional quantities: mL, L, cm 3, m 3,… Volume is measured in three dimensional quantities: mL, L, cm 3, m 3,… Mass is measured in g, kg,… Mass is measured in g, kg,… Density is a “derived unit” of g/ml or g/cm 3 or g/L or kg/L,…. Density is a “derived unit” of g/ml or g/cm 3 or g/L or kg/L,…. Density = Mass Volume Mass = Density x Volume Volume = Mass Density

3. Density Practice for extra credit. 1. Illegal ivory is sometimes detected on the basis of density. What is the density of a sample of ivory whose volume is 14.5 cm 3 and whose mass is 26.8 g? 2. An archeologist finds that a piece of pottery has a mass of 0.61 g and a volume of 0.26 cm 3. What is the density of the pottery? 3. Calcium chloride is used as a de-icer on roads in winter. It has a density of 2.50 g/cm 3. What is the volume of 7.91 g of this substance?

4. Density = mass/volume 1. Illegal ivory is sometimes detected on the basis of density. What is the density of a sample of ivory whose volume is 14.5 cm 3 and whose mass is 26.8 g? Density = Mass Volume Mass = Density x Volume Volume = Mass Density mass = 26.8 g density = ? Volume = 14.5 cm 3 density = 26.8 g 14.5 cm 3 = 1.85 g/cm 3

5. Density = mass/volume 1. An archeologist finds that a piece of pottery has a mass of 0.61 g and a volume of 0.26 cm 3. What is the density of the pottery? Density = Mass Volume Mass = Density x Volume Volume = Mass Density mass = 0.61 g density = ? Volume = 0.26 cm 3 density = 0.61g 0.26 cm 3 = 2.3 g/cm 3

6. Density = mass/volume 1. Calcium chloride is used as a de-icer on roads in winter. It has a density of 2.50 g/cm 3. What is the volume of 7.91 g of this substance? Density = Mass Volume = Mass Density mass = volume x density mass = 7.91 g density = 2.50 g/cm 3 Volume = ? Volume = 7.91 g 2.50 g/cm 3 Volume = 3.16 cm 3

7. Density Lab You have 5 objects You have 5 objects Find the mass of each objectFind the mass of each object Find the volume of each objectFind the volume of each object Calculate the densityCalculate the density Each partner takes responsibility for one portion of the lab Each partner takes responsibility for one portion of the lab Summary of the introductionSummary of the introduction Pre-lab questionPre-lab question DataData Conclusion questions.Conclusion questions. Lab is due in ONE WEEK Lab is due in ONE WEEK