1. Due Today: Density Part 1 Pre-Lab Homework: 1. Density Part-2 Pre Lab DENSITY PART I

2.  Collect data to:  Determine the density of an unknown liquid  Determine the density of rubber stoppers OBJECTIVE

3.  Mass – determined by an analytical balance  Volume – determined by graduated glassware  RECORD THE TEMPERATURE OF WATER!  RECORD YOUR UNKNOWN KEY TERMS

4.  Density of an Unknown Solution 1. Graduated Cylinder Method 2. Buret Method PROCEDURE NOTES

5. 1. Graduated Cylinder Method  Record the mass of the liquid on the balance  Record the volume REMAINING in the graduated cylinder  Measure from the bottom of the meniscus  Measure to the nearest 0.1 mL PROCEDURE NOTES

6. 2. Buret Method  Record the mass of the liquid in the beaker  Record the volume DISPENSED from the buret  Measure from the bottom of the meniscus  Measure to the nearest 0.01 mL  DO NOT record the volume remaining in the buret PROCEDURE NOTES

7.  Density of Rubber 3. Displaced Volume Method 4. Displaced Mass Method PROCEDURE NOTES

8. 1. Displaced Volume Method  Record the mass of each stopper  Record the volume displaced when the stoppers are added  Measure to the nearest 0.1 mL PROCEDURE NOTES

9. 2. Displaced Mass Method  Fill the flask entirely  Make sure there are NO air bubbles  Record the flask without the rubber stopper  Make sure the glass stopper is on the flask  Record the flask with the rubber stoppers  Dry off the flask before placing it on the balance PROCEDURE NOTES

10.  Blue and Yellow liquid  Down the drain  Green liquid  Waste container in hood WASTE

11.  Green Solution:  Isopropyl Alcohol  Danger  Flammable Liquid  Mild Skin Irritation  Harmful if Swallowed RISK ASSESSMENT