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 Introductory Physics 110Hunter CollegeGas PropertiesIntroductionOne of the states of matter, gases are considerably less dense than liquids or solids, and particles of a gas often exhibit minimal interactions with one another. Many real gases, under certain conditions, can be reasonably approximated as an ideal gas, which is composed of randomly moving point particles, and only interact via elastic collisions with walls/boundaries and one another. Classical studies on gases in the 17th and 18th centuries found many empirical relations between the volume of a gas, the pressure it exerts, and its temperature. Robert Boyle discovered that, if the temperature and amount of a gas remains constant in a closed system, then the absolute pressure exerted is inversely proportional to the volume:P=aV, assuming T=const.where a is a constant, and T is the absolute temperature in Kelvin.Definition: The Kelvin scale is an absolute temperature scale, defined as having an absolute zero. It is related to the Celsius scale via the following relation: TK=Tc+273.15such that the freezing point of water (0°C) is at 273.15K.Jacques Charles found a direct relation between the volume of a gas and its temperature, keeping pressure constant:V=b*T, assuming P=const.where b is a proportionality constant. Amadeo Avogrado hypothesized that equal volumes of all ideal gases, at the same temperature and pressure, contain the same number of particles:V= c*nwhere c is a proportionality constant, and n is the number of particles in moles. Definition: A mole is a standard (SI) unit of quantity, comprising 6.02 x 1023 particles. That is to say, one mole of water contains 6.02 x 1023 water molecules, and a mole of copper contains 6.02 x 1023 atoms. Combining Boyle’s, Charles’, and Avogadro’s laws, we arrive at the ideal gas equation:PV=nRTwhere R is the ideal gas constant, defined as 8.314 J?K-1?mol-1. This lab simulation, and following experiments, will attempt to display these relations qualitatively.Pre-Lab Questions (show your work)An ideal gas is kept under constant temperature inside a piston. Initially, the gas takes up 3 m3 of space, and is under 105kPa of pressure. What is the new volume of the gas if the pressure is increased to 160kPa?At what temperature will 56.8 moles of Nitrogen gas occupy .24 m3 at 151.685kPa?ProcedureOpen the simulation here. Open the Ideal tab. Notice all the components of the simulation: A chamber with an expandable volume, Thermometer to measure temperature, a gauge to measure pressure (in atm and kPa), a bucket with fire or ice to increase/decrease the temperature, and a pump to inject particles into the chamber. The injection pump The Pressure gaugePart 1: Change the injected particles to heavy particles. Make sure that Nothing is held constant, and that the collision counter is pressed. With the chamber initially empty, pump the handle fully once. Wait 20 seconds for the particles to diffuse through the chamber and equilibrate, then press play on the collision counter. After 10s (simulated as 10ps), record the wall collisions, temperature, and pressure.Pump the handle 3 more times (total of 4). Wait 20 seconds to allow the system to equilibrate, and press play on the counter. Record the collisions, temperature, and pressure (in kPa).Now pump the handle 4 more times (total of 8). Wait 20 seconds, then measure the collisions. Record.Questions for Part 1:Compare your answers for 1A, 1B and 1C. What do you notice about the temperature? What about the pressure? What about the wall collisions?Predict what will happen if you pumped the handle 16 times (predict temperature, pressure in kPa and collisions). Attempt this in the simulation. Record your findings. Were you close?Part 2: Constant VolumeReset the system using . Pump the handle two times. In the Hold Constant Box, make sure Volume, Width, and Collision counter is ticked. Use the bucket to lower the temperature to 50K. Wait 30 seconds to let the system equilibrate, then record the number of collisions and the pressure (in kPa).Do this for at least 5 more temperatures. TemperatureNumber of collisionsPressureQuestion for Part 2:What relationship do you see between the number of collisions and the pressure?Part 3: Constant Temperature:Reset the system using . Pump the handle two times, and set the temperature to 300K. In the Hold Constant Box, make sure Temperature, and Collision counter is ticked. You can now pull the handle on the left to change the volume of the box. Note how the Pressure changes with varying volume.Move the volume to 10nm. Wait 20 seconds, then record the number of collisions in a 10s (10ps simulated) period. Do this for at least 5 more volumes. The volume handleVolumeNumber of collisionsPressureQuestions for Part 3:What happens to the pressure as you vary the volume? Plot the pressure versus the volume, and describe the graph.Repeat A-C, now with a temperature of 400K. Plot your 300K and 400K on the same graph. What happens to the graph at increased temperature?Part 4:Reset the system with . Pump the handle three times. In the Hold Constant Box, make sure that Pressure ?V, Width, and Collision counter is ticked.This time, you can change the temperature of the gas using the bucket at the bottom. As you do, note what happens to the volume and pressure of the gas.Change the temperature to 280K. Wait 20 seconds, then record the number of collisions in a 10s (10ps) period. Do this for at least 5 more temperatures. The temperature controlTemperatureVolumeNumber of collisionsPressureQuestions for Part 4:Plot the Volume versus Temperature. What does the graph look like?What happens to the pressure as the temperature changes?Post lab questions:How would changing the species of gas from heavy to light change your results in this experiment?We did not explore the relationship between the number (moles) and temperature, moles and volume or moles and pressure. Can you design an experiment similar to this one to show any one of these relationships? ................
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