Who wants to be a Chemist? By receiving an A on the Weather Exam?

Who wants an A on the Weather Exam? Ask Mr. G Ask The Class Eliminate 2 Answers Question Point Value 20 points 15 points 14 points 13 points 12 points 11 points 10 points 9 points 8 points 7 points 6 points 5 points 4 points 3 points 2 points 1 point Lifelines 50:50

Total Possible points = 140 pts As a class, if you earn 100% or 140 pts = 4 exam bonus pts 90% or 126 pts = 3 exam bonus pts 80% or 112 pts = 2 exam bonus pts 70% or 98 pts = 1 exam bonus pt Below 98 pts = 0 quiz bonus pts

Game show rules… There are 3 lifelines, which can only be used once each. Lifelines cannot be used on the 20pt question. Each member of the groups is required to participate! Rude or disruptive behavior to your fellow classmates will result in voiding of individual bonus point potential earnings. No student can use notes, or books. Notebook paper and calculators are allowed.

Lets start with something easy!

What is Charles's Law? 1 POINT Ask the classEliminate 2 Answers Ask Mr. G Charless law: For a given sample of gas at a certain pressure, the volume of gas is directly proportional to its Kelvin temperature. Or V 1 /T 1 = V 2 /T 2

A sample of gas has a volume of 120 L at a temperature of 40 °C. The temperature drops to –10 °C. What is the new volume of the gas? (A) L (B) L (C) 30 L (D) Not enough information provided 2 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: B

Kinetic Molecular Theory describes gases as a large number of small particles, all of which are in ______ and _______ motion. 3 POINTS Ask the classEliminate 2 Answers Ask Mr. G Constant and Random

What is Boyles Law? 4 POINTS Ask the classEliminate 2 Answers Ask Mr. G Boyles law: The pressure of a given amount of gas is inversely proportional to its volume, if the temperature and amount of gas are not changed. The relationship between pressure and volume can be expressed as PV = k, or P = k(1/V), where k is the proportionality constant. Or P 1 V 1 = P 2 V 2

A balloon full of gas occupies 12.5 L, and the pressure on the outside of the balloon is 1.6 atm. What is the pressure on the outside of the balloon if its new volume is 2.5 L? (A) 0.32 atm (B) 16 atm (C) 8 atm (D) Not enough information provided 5 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: C

Which gas atoms move the fastest? (A) He (B) Kr (C) Ar (D) Ne 6 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: A

What is Gay-Lussacs Law? 7 POINTS Ask the classEliminate 2 Answers Ask Mr. G Gay-Lussacs law: The pressure of a given amount of gas is directly proportional to temperature if the gas volume and amount of gas do not change and if the temperature is expressed in kelvins. Or P 1 /T 1 = P 2 /T 2

In the factory, a potato chip bag is filled at 1.0 atm, and the temperature is 25°C. In a cars trunk the temperature rises to 60°C. What is the new pressure? (A) 0.89 atm (B) 1.12 atm (C) 1.38 atm (D) Not enough information provided 8 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: B

What is the Combined Gas Law? 9 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Combined Gas Law states the ratio between the pressure-volume product and the temperature of a system remains constant. Or P 1 V 1 /T 1 = P 2 V 2 /T 2

A sample of neon gas occupies a volume of 3.0 L at 300 K and 1.5 atm. Suppose you increase the temperature to 600 K and decrease the pressure to 0.50 atm, what is the new volume? (A) 18 L (B) 4.5 L (C) 2 L (D) Not enough information provided 10 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: A

Now for some harder questions…

Which Law states: the volume of gas is directly proportional to its temperature in K? (A) Boyles (B) Ideal (C) Charles (D) Gay-Lussacs 11 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: C

60mL of gas is cooled from 27°C to 2.0°C, what is the new volume? (A) 65mL (B) 55mL (C) 40mL (D) 70mL 12 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: B

You cap a 2.0 L plastic bottle on a mountaintop where the air pressure is 0.85 atm and the temperature is 3°C. How many moles of gas are in the bottle? (A) 1.35 moles (B) moles (C) moles (D) 18.2 moles 13 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: C

A balloon with a volume of 1.0 atm is taken into a chamber where the volume changes to 2.5 ml, what is the new pressure? (A) 3,000 atm (B) 3.0 atm (C) 0.33 atm (D) 1.5 atm 14 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: A

A vehicles tire in the morning had pressure of °C. In the afternoon the pressure was 2.17 atm. What was the temperature in the afternoon? (A) 265 K (B) 323 K (C) 301 K (D) 317 K 15 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: D

How many molecules of He gas are in a 25,000 L weather balloon at 2.0 atm and 25°C? (A) 3.85 x molecules (B) 7.00 x molecules (C) 9.67 x molecules (D) 1.27 x molecules 20 POINTS Ask the classEliminate 2 Answers Ask Mr. G The Correct Answer is: D

Are you ready for an A on your Weather Exam?