80 likes | 246 Views
Chapter 19. Temperature EXAMPLES. Chapter 19: Temperature: Examples. Example 19.1 Converting Temperatures. (A). Convert 50 o F to Celsius and Kelvins T C = T K – 273.15 T K = T C + 273.15 T K = 10 o C + 273.15 = 283.15 o C
E N D
Chapter 19 Temperature EXAMPLES
Example 19.1 Converting Temperatures • (A). Convert 50oF to Celsius and Kelvins • TC = TK – 273.15 TK = TC + 273.15 TK = 10oC + 273.15 = 283.15oC • (B). At which temperature TF = TC
Example 19.2 Heating a Pan of Water • A pan of water is heated from 20oC to 80oC . What is the change in its temperature on the Kelvin scale and on the Fahrenheit scale.
Example 19.3 Filling a Scuba Tank • A scuba tank can hold 60.0 ft3 of air at atmospheric pressure (14.7lb/in2) and 22oC (295K). When this volume of air is compressed to a pressure of 3000 lb/in2 and stored in 10.0L (0.350ft3) tank, the air becomes so hot that the tank must be allowed to cool before it can be used. Before the air cools what is its temperature? • Assume air behaves as an ideal gas: PV = nRT nR = PV/T
Example 19.4 Don’t Throw a Closed glass Jar Into a Campfire. • What can happen if you did throw an empty glass jar, with lid on tight, into a fire, and Why? • The inside of the jar is not empty. It is filled with air. As the fire heats the air inside, its temperature rises. • Volume inside the glass jar changes only slightly due to the heating. • According to Gay-Lussac’s Lawthe pressure P of the air inside the jar can increase dramatically, enough to cause the jar to explode, throwing glass pieces outward!!
Example 19.5 Heating a Spray Can • A spray can containing a propellant gas at twice atmospheric pressure (202kPa) and having a volume of 125c.c is at 22oC. It is the tossed into an open fire. When the temperature of the gas in the can reaches 195oC, what is the pressure inside the can. Assume any change in the volume of the can is negligible. • The gas in the can could be treated as an ideal gas: PV = nRT nR = PV/T • No gas escapes during the compression so nR remains constant, and Vi = Vf
Material for the 2nd Midterm • Material from the book to Study!!! • Objective Questions: 3-10 • Conceptual Questions: 2-5 • Problems: 2-4-5-6-21-23-25-30