1. Density of different materials

2. Chem Catalyst

3. Chem catalyst 1.How can a ship made out of steel (more dense than water) carrying crude oil or containers full of goods (more dense than water) float on water? 2.Why do these people have an easier time floating on the water than somebody at the local swimming pool?

4. Goals Determine densities of regularly shaped objects Determine the difference between density of freshwater and saltwater Differentiate between density of components and density of the whole

5. DENSITY OF THE MATERIAL IN A TIN CAN

6. Volume equations of regular shapes Cylinder: V = πr 2 h Pyramid: V = ⅓Bh Rectangular Prism: V = Lwh Cone: V = ⅓πr 2 Sphere: V = ⁴⁄ 3 πr³

7. What do the symbols mean? V = volume r= radius of a circle B = area of the base h = height (length perpendicular to the base) L = length w = width Length, width and height are measurements perpendicular to each other

8. Finding the Radius Use circumference and diameter to find radius, do not EYEBALL it! 1.Use string to determine circumference 2.Divide the circumference by π to get diameter 3.Divide diameter in half to get radius

9. Procedure For each object given: 1.Describe the shape of the container: 2.Describe object or name the contents 3.State the equation to find the volume of the shape of the can: 4.Determine which measurements are needed to calculate the volume of the can

10. Procedure, part 2 5. For each measurement, identify the unit of measure to be used: 6.Perform measurements and list in the chart below with the appropriate units 7.Calculate volume of object 8.Determine mass of object (!!warning!!) Some objects have the mass measurement on the label. DO NOT PUT LARGE OBJECTS on digital scales 9.Determine the density of object

11. Objects Chart Object 1 (Describe__________) Measurement Description Value of meas. (#) Unit Description Obj 2 (Describe ____________) Measurement Description Value of meas. (#) Unit Description Calculations: Density value, with units: Calculations: Density value, with units:

12. Determine the density of tap water and saltwater Goggles are needed for this lab(Why?) Materials needed – 100 ml graduated cylinder – 2 identical 100 ml griffin beakers – 50-60 ml of tap water – 4 grams of salt – Stirrer rod – Hot plate – thermometer

13. Steps to be accomplished 1.Determine the mass of an empty beaker 2.Determine the mass of 50-60 ml of tap water 3.Determine the volume, density of 50-60 ml of tap water 4.Heat up to 30⁰ C and dissolve all salt into 50-60 ml of tap water. 5.Determine mass, volume and density of saltwater solution 6.TURN OFF THE HOT PLATE, clean and put equipment back

14. Salt water Type of Water VolumeMassDensityTemp. Tap Water Before heating Saltwater solution 30⁰ Make sure values for saltwater are accomplished After Heating

15. Remember Turn off hot plate when you are done!!! Rinse and put away glassware Put goggles away in UV cabinets