Presentation on theme: "Final Jeopardy Question Gas Law Concepts Gas Law Calc- ulations 500 Gas Law Demos SCUBA & Green- House Effect 100 200 300 400 500 400 300 200 100 STP &"— Presentation transcript:
Final Jeopardy Question Gas Law Concepts Gas Law Calc- ulations 500 Gas Law Demos SCUBA & Green- House Effect 100 200 300 400 500 400 300 200 100 STP & Temp. Conver- sions
Experiment: Student A begins boiling a cup of water in Boston while Student B does the same at the same time in Denver. Which student’s water will boil first and WHY? Back
Student B (in Denver) since the atmospheric pressure is lower in Denver (higher altitude), water here will boil first. The water in Denver will not need to meet as high of an atmospheric pressure as that in Boston. Back
As you go down in elevation, what happens to the atmospheric pressure and WHY? Back
Pressure increases as elevation decreases because the air is more dense at lower elevations. Back
What does John’s Law state and what is the equation? Back
As pressure goes up, temperature goes up (and vice-versa) at constant volume. P 1 = P 2 T 1 T 2 Back
At constant pressure, as temperature increases, volume increases (and vice- versa). Back
A sample of gas has a volume of 23 mL at 39 o C and 890 mm Hg. This sample is cooled down to 11 o C and now has a volume of 150 mL. What is the new pressure? Back
Use the combined gas law since all variables are changing… P 1 V 1 = P 2 V 2 T 1 T 2 890 mm Hg ( 23 mL)=P 2 (150 mL) 312 K284 K P 2 = 124.22 mm Hg Back
A 50 L container is filled with a gas to a pressure of 4.7 atm at 32 o C. At what temperature IN DEGREES CELSIUS will the pressure inside the container be 3.5 atm with a volume of 50 L? Back
Volume is constant, so use John’s law. P 1 = P 2 4.7 atm = 3.5 atm T 1 T 2 305 KT 2 T 2 = 227.13 K = -45.87 o C Back
A gas occupies a volume of 34 mL at 21.8 o C. To what temperature (in Kelvin) must the gas be raised to have a volume of 86 mL? Assume constant pressure. Back
Pressure is constant, so use Charles’ law. V 1 = V 2 34 mL = 86 mL T 1 T 2 294.8 KT 2 T 2 = 745.67 K Back
A balloon has a volume of 6L at 13.2 psi. If the balloon was brought to a pressure of 9.3 psi, what would the new volume be (assume constant temp).
Temp is constant, so use Boyle’s law. P 1 V 1 = P 2 V 2 13.2 psi (6L) = 9.3 psi (V 2 ) V 2 = 8.52 L Back
Whose law is being used in the following situation… A sample of gas in a flexible container occupies 46.5 mL at standard pressure. What volume will it take up if the pressure was increased to 3 atm? Assume constant temp. Back
Temp is held constant, so it is Boyle’s law. Back
Explain how a straw works – and DO NOT USE THE WORD “SUCK”. Back
When you inhale, your body takes in the air that is in a straw, creating less pressure in the straw. Since the pressure in the straw is less than the pressure outside the straw, the atmospheric pressure PUSHES the liquid into the straw so you can enjoy! Thank heaven for atmospheric pressure! Back
Explain the egg in flask demo. AND DO NOT USE THE PHRASE “SUCKED IN”. Back
In the egg demo, water was heated in the flask. Since temp increased in the flask, the pressure also increased. The flask was then taken away from the heat, and an egg was placed on top. The flask cools, so the pressure inside the flask decreased. Since the pressure inside the flask decreased, the atmospheric pressure outside the flask PUSHED the egg into the flask. Back
A pressure apparatus that contains a sample of gas at a fixed volume is first placed into a container of hot water. It is then plunged into a container of liquid nitrogen. What happens to the pressure and why? Back
This is an example of John’s law – when temp goes down, pressure goes down. Back
Explain why the Ivory soap expanded in the microwave.
Since temp increased, so does volume. This is Charles’ law. Back
What will happen to the volume of a balloon if it is placed into a bell jar (vacuum pump) and the pump is turned on. Hint: in a bell jar, the pressure inside decreases. Back
The volume of the balloon will increase. This is Boyle’s law… as P decreases, V increases and vice versa. Back
What is the relationship between pressure and depth as you descend during a SCUBA dive? Back
Every 10 meters (or 32 feet) you descend is an increase in 1 atm. Back
What would happen if someone ascended too quickly during a SCUBA dive? Back
The lungs of the diver can expand too quickly and tear. Since pressure decreases as you ascend, volume will increase (Boyle’s law). Back
What has caused an increase in global warming (greenhouse effect) over the past 100 years?
Back Gases in the earth’s atmosphere absorb heat coming from the earth’s surface and reflect it back to the earth. This warms the earth. Through our daily activities such as driving cars, using a BBQ grill, using air conditioners and refrigerators, more gases are emitted into the environment which increases global warming.
Back What is the relationship between the solubility of a gas and depth of descent?
Back As you descend further (elevation decreases), the solubility of a gas increases. So, at deeper depths, you will have more gas dissolved in your body.
What is one characteristic of the ozone layer? Back
*absorbs UV light *thin layer surrounding the earth *depletion could increase the amount of UV rays hitting the earth which could mean increased mutations. Back
If you are making pasta in Los Angeles and at the same time, your best friend in Colorado Springs is doing the exact same thing, whose pasta will cook first and why? Back
LOS ANGELES – the boiling point of water in Los Angeles is higher than the boiling point of water in Colorado Springs. WHY? Water boils when the vapor pressure equals the atmospheric pressure. Because the atmospheric pressure in L.A. is higher than that in Colorado Springs, so even though the water in L.A. will boil second, it will have a higher temperature providing more heat. THUS, the pasta in L.A. will be done first. Back
This Jeopardy Game was Created by: Sara Feltman, 5th Grade Teacher Scott Elementary School 1999-2000 School Year Revised: RLipkowitz 2000