Gas Law Problems 1
The temperature of a sample of I2 is changed, causing a change in volume from 45.4 L to 98.37 L. If the starting temperature was 1059.03 K, what is the final temperature in kelvins?
2290 K
2294.64 K
A sample of SF6 in a 99.7 L metal cylinder at 573 kPa has its temperature changed from 741 K to 425 K while its volume is simultaneously changed by a piston to 32.4 L. What is the final pressure in kilopascals?
1010 kPa
Describe a negative feedback loop that involves the carbon or water cycle. How does this feedback loop help stabilize Earth's climate?
Various answers:
- Evaporation -> condensation -> precipitation -> evaporation
- Combustion -> photosynthesis -> combustion
What does pH measure?
pH measures the concentration of H+ ions, or protons. Since the formula is -log(H+), if there are more H+ ions, then the pH will go down. More H+ ions means it is more acidic, so a lower pH means the acidity is higher. 7 is generally considered neutral, and anything below is acidic whereas anything above is basic.
The temperature of a sample of F2 is changed, causing a change in volume from 58.1 L to 59.28 L. If the starting temperature was 1005.51 K, what is the final temperature in kelvins?
1030 K
1025.93 K
The pressure of a 2.724 mol sample of N2O in a 61.7 L container is measured to be 553.26 kPa. What is the temperature of this gas in kelvins?
1510 K
Explain the role of the ocean in the carbon cycle. How does it interact with carbon in the atmosphere, and how might this change as there is more CO2 in the atmosphere?
The ocean absorbs CO2 from the atmosphere and can act as a carbon sink. When there is more CO2, the ocean will absorb more CO2, and this will lead to more water reacting with CO2 and forming carbonic acid. When there is more carbonic acid, the pH of the ocean will go down, harming many marine organisms and disrupting food chains.
What is the difference between an acid and a base?
An acid is a "proton donor" and gives up H+ ions. A base is a "proton receiver" and takes H+ ions, making a solution less acidic if it is a strong enough base.
A sample of AsH3 in a metal container at 150.2 kPa has its temperature changed from 769 K to 502.74 K. What is the final pressure in kilopascals?
98.2 kPa
98.19 kPa
A sample of CH4 in a 3.86 L metal cylinder at 727 kPa has its temperature changed from 487.7 K to 995.17 K while its volume is simultaneously changed by a piston to 50.69 L. What is the final pressure in kilopascals?
113 kPa
Describe a positive feedback loop that involves the carbon or water cycle. How does this feedback loop destabilize the Earth's natural balance?
Various answers:
- Warmer temperatures -> more evaporation -> more water vapor in the air -> warmer temperatures
- Forest fire -> more CO2 -> fewer plants to process CO2 -> warmer temperatures -> more forest fires
Imagine Earth's atmosphere had no greenhouse gases. What would the climate be like?
Without greenhouse gases, infrared radiation would pass through our atmosphere and return to space. This would cause the Earth to be frigid and cold during the night when there is no sunlight. We would be very much "not alive."
A sample of ClF5 experiences a change in pressure from 757 kPa to 128.8 kPa. If its new volume is 40.029 L, what was its original volume in liters?
6.81 L
A 4.1621 mol sample of SeF6 is in a 42.119 L container. What is the pressure of this gas in kilopascals at 373.3 K?
306.5 kPa
How does increased air temperature influence humidity in the water cycle? Describe how it can change evaporation and precipitation patterns.
Increased air temperature leads to a larger carrying capacity for water vapor in the air (i.e. if it's hotter, the air can hold more water). This can lead to more evaporation, since there is more "room" in the air for water vapor. This also means that, since the air can hold more water vapor, precipitation patterns will be disrupted, potentially leading to drought.
Explain how increased carbon dioxide in the atmosphere leads to ocean acidification. Include the chemical process that takes place when CO₂ dissolves in seawater.
CO2 and water react to form carbonic acid. This lowers the pH of the ocean, making it more acidic, and harming sea creatures. Additionally, when the pH is lower, carbonic acid breaks down in bicarbonate more, instead of carbonate, and carbonate is needed for shell creation. It's a double whammy.
A sample of C2H4O experiences a change in volume from 84.98 L to 74.024 L. If its new pressure is 680.5 kPa, what was its original pressure in kilopascals?
592.8 kPa
592.77 kPa
The temperature of a 7.49 L sample of BrCl is changed, causing a change in pressure from 429 kPa to 849 kPa. If its new temperature is 849 K and its new volume is 57.619 L, what was its original temperature in kelvins?
55.8 K
Humans are adding large amounts of carbon dioxide to the atmosphere. Describe how this disrupts the natural carbon cycle and leads to changes in Earth’s climate.
In the balanced carbon cycle, CO2 is constantly moving from the atmosphere back into solid form, such as sugar, plants/animals and potentially rocks/fossil fuels. When there is too much CO2, this balance is disrupted, and the natural processes cannot move this CO2 out of the atmosphere. When this happens, CO2 levels rise, and since CO2 is a greenhouse gas, temperatures go up. CO2, and other greenhouse gas molecules like water, have special geometry which allows them to vibrate when they interact with thermal energy/infrared radiation. When this happens, the energy gets trapped in the atmosphere, instead of passing through the molecule and going back into space. This change in temperature can cause many disruptions to the natural balance on Earth.
Why do greenhouse gases trap heat in Earth’s atmosphere? Explain the process using the behavior of infrared radiation and the role of gases like CO₂ and water vapor.
CO2 and Water Vapor both have a geometry that allows them to vibrate when they interact with infrared radiation. The majority of air is O2 and N2, which are both symmetrical, linear molecules. These do not vibrate/jiggle when they come into contact with infrared radiation, so the energy passes through them and returns to space. Water vapor especially, with it's "bent" geometry, allows it to wiggle and move, which stores the energy and traps it in our atmosphere.