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CHEM 110Gases (Key)Ch. 9 Gas Laws 1. A balloon has a volume of 2.50 L indoors at 22 o C. If the balloon is taken outdoors on a cold day in Escanaba where the air temperature is -15 o C (5 o F), what will its volume be in liters? V 1 T 1 = V 2 T 2 V 1 T 2 = V 2 T 1 V 2 = V 1 T 2 T 1 = ( 2.5 L )( 258 K ) ( 295 K ) = 2.18 L V = 2.18 L 2. A sample of helium at a pressure of 745 torr and in a volume of 2.58 L was heated from 24.0 to 75.0 o C. What was the final pressure (in atm) of the helium? P 1 T 1 = P 2 T 2 P 1 T 2 = P 2 T 1 P 2 = P 1 T 2 T 1 = ( 745 torr )( 348 K ) ( 297 K ) = 873 torr P = 873 torr 3. There is an unknown volume of gas at a pressure of 0.5 atm and a temperature of 325 K. If the pressure is raised to 1.2 atm, temperature is lowered to 320 K, and the final volume is measured to be 48 liters, what was the initial volume of the gas (in liters)? Initial Final P (atm) 0.5 1.2 T (K) 325 320 V (L) ? 48 P 1 V 1 T 1 = P 2 V 2 T 2 P 1 V 1 T 2 = P 2 V 2 T 1 V 1 = P 2 V 2 T 1 P 1 T 2 = ( 1.2 atm )( 48 L )( 325 K ) ( 0.5 atm ) ( 320 K ) = 112 L