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Directions: ❏ 1. Observe each of the four beakers color and record in the data table below. ❏ 2. Next, each group member will take a cotton swab and at the same time all members will draw 1 line across the lab table. ❏ 3. Record the order at which each substance evaporated. ❏ 4. Ask the teacher for a wet wipe to clean the area of the evaporated substances ❏ 4. Identify each substance using Table H in your reference table. Substance Color Evaporation Order Identification of Substance A B C D How did you determine each substance? 1 Questions Use Table H to answer the following questions. 1. What is the title of the graph? 2. What quantity is graphed on the x axis? What units is it measured in? 3. What is the range of temperatures? 4. What quantity is shown on the y axis? 5. Looking at Table A, what is important about 101.3 kPa? 6. What is the vapor pressure of propanone at 45oC? 7. What is the vapor pressure of ethanol at 90oC? 8. What is the vapor pressure of each substance at 75° C? ethanoic acid _______ water _______ ethanol _______ propanone _______ 9. What is the temperature corresponding to 101.3 kPa for each of the substances? ethanoic acid _______ water _______ ethanol _______ propanone _______ 2 10. Unit conversions STANDARD PRESSURE: is the normal atmospheric pressure at sea level and is expressed as: 1 atm =101.3 kPa =760 mmHg =760 torr A. How many mmHg are equal to 1.25 atm? To solve: 1. Start with the fact that 1 atm=760 mmHg 2. Set up ratio 3. solve for x by cross multiplying then divide 1.25 atm = _x__ 1 atm 760 mmHg x=950 mmHg B. How many atm are equal to 430 kPa? To solve: 4. Start with the fact that 1 atm=430 kPa 5. Set up ratio 6. solve for x by cross multiplying then divide X __ = 1 atm _430 kPa__ 760 mmHg x=0.57 atm 3 C. How many mmHg are equal to 136 kPa? D. How many kPa are equal to 1.55 atm? E. How many torr are equal to 1.55 atm? 4