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DATE:. 04/01/2014. DO NOW:. OBJECTIVES. Explain the relationship between temperature and volume. Calculate temperature and volume using Charles’s Law. 1. What happens to a helium balloon if you go out in cold weather?. DATE:. 04/02/2014. DO NOW:. OBJECTIVES.
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DATE: 04/01/2014 DO NOW: OBJECTIVES • Explain the relationship between temperature and volume. • Calculate temperature and volume using Charles’s Law. 1. What happens to a helium balloon if you go out in cold weather?
DATE: 04/02/2014 DO NOW: OBJECTIVES • Explain the relationship between temperature and volume. • Calculate temperature and volume using Charles’s Law. 1. What is the relationship between temperature and volume?
Gases • The balloon will shrink (volume decreases), but WHY?
Gases • The decrease in temperature causes the gas molecules to slow down. • Slower moving molecules= fewer collisions
Review: Boyle’s Law • Look at Figure 13.1 on page 442 • Look specifically at the graph • Discuss with your partner… • What does the SHAPE of the line in the graph mean to you?
Review: Boyle’s Law • Pressure and Volume are INVERSELY proportional. • ANY graph with a line shaped like the one in figure 13.1 is indicating an inverse relationship.
Charles’s Law • Shows the relationship between the volume of a gas and its temperature at a constant pressure.
Charles’s Law • Temperature and Volume are directly proportional. • As the Temperature increases, the Volume will increase. • As the Temperature decreases, the Volume will decrease. • Pressure and Number of molecules must be constant.
Charles’s Law • Look at Figure 13.2 on page 445 • Look specifically at the graph • Discuss with your partner… • What does the SHAPE of the line in the graph mean to you?
Charles’s Law • Temperature and Volume are Directly proportional. • ANY graph with a line shaped like the one in figure 13.2 is indicating a direct relationship.
Charles’s Law V 1 = V 2 T 1 T 2 **The UNITS for T1and V1 must match the units for T2and V2.
Charles’s Law • Discuss with your partner: • When the temperature (x-axis) doubles from 500 Kelvin (K) to • 1000 K, what happens to the • volume? Be specific. • Be prepared to share with the class!
Charles’s Law With your partner, complete this sample problem in your notes: What is the volume of the air in a Balloon that occupies .620 L at 25◦C If the temperature is lowered to 0.00◦C? *Before you calculate, convert from Celsius to Kelvin
Charles’s Law T1= 25◦C + 273= 298K T2 = 0.00◦C + 273= 273K V2 = V1T2= (0.620L) (273K) T1 298K V2 = 0.57 L