Diffusion Gizmos

Name: Date: Shreya 10 15 25 Student Exploration: Diffusion Directions: Follow the instructions to go through the simulation. Respond to the questions and prompts in the orange boxes. Vocabulary: absolute zero, controlled experiment, diffusion, dynamic equilibrium, Kelvin scale, kinetic energy Prior Knowledge Question (Do this BEFORE using the Gizmo.) Have you ever smelled microwave popcorn? The oddly enticing scent can fill a whole house. How do you think the smell of popcorn spreads through the air? the air 18 9 Ideas p from the bagspreads Gizmo Warm-up Smells are carried by tiny particles that move through the air. The Diffusion Gizmo shows gas particles in a chamber that is divided into two regions by a partial wall. Click Play ( ) and observe. 1. Describe the motion of the gas particles. The particles to start bounce around 2. Over time, what is happening? Overtime after they spread out more the in particles move This process, which particles move from an area of slower high concentration (region A) to an area of low concentration (region B), is called diffusion. 3. Select the BAR CHART tab, and observe the chart for a few minutes. After the first 30 seconds or so, how much do the numbers of particles in each region change? After the first side A loses while side equilibrium. When the numbers don’t change much, the particles are said to be in dynamic particles B gains 30 seconds 4. Click Pause ( ), and select the GRAPH tab. What does the graph tell you about the number of particles in region A? The graph tells me that in 30 seconds side A lost about 25 of its concentration of gas Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved Get the Gizmo ready: Activity A: Temperature and diffusion ● Click Reset ( ). ● Set the Wall to 100%. Introduction: In this Gizmo, temperature is measured on the Kelvin scale. On this scale, 0 K represents absolute zero, the coldest possible temperature. Water freezes at 273.15 K (0 °C), and water boils at 373.15 K (100 °C). Question: How does temperature affect the rate of diffusion? 1. Observe: Set the temperature (Temp.) to 100 K, and press Play. Observe the motion of particles. Click Reset. Then set the temperature to 600 K, click Play, and observe. How does the temperature of the gas relate to the motion of the particles? The warmer the temperature of gas the faster of wallKinetic energy tokinetic other diffuse particles Thethe temperature of a gas is a measure of the average energyside of a set of particles. (KE) depends on the velocity and mass of the particles (KE = mv2 / 2). 2. Form hypothesis: How do you think temperature will affect the rate of diffusion? feel my examinations will stay the same the warmer the temperature is the faster the particles will move I 3. Experiment: Click Reset. Set the Wall to 50%, x in A to 100, y in B to 0, Temp. to 100 K, and Particle mass to 15 amu (atomic mass units). Select the TABLE tab. Press Play. Click Pause when x in A first reaches 55% or below. Record this Time to reach equilibrium in the left table below. Repeat four more times at 100 K, and then run five trials with the temperature set to 600 K. Temp = 100 K experiment Trial Time to reach equilibrium Temp = 600 K experiment Trial 1 1 2 2 3 4 5 1494 19 3 4 5 Time to reach equilibrium 92 103 102 88 91 Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved 4. Calculate: Find the average time to reach equilibrium for each experiment: A. Average time to reach equilibrium at 100 K: B. Average time to reach equilibrium at 600 K: 146.8 seconds 95.2 seconds 5. Draw conclusions: Compare the average times to reach equilibrium for each temperature. A. How did temperature affect the rate of diffusion? B. Why do you think this was the case? reaching equilibrium faster 6. Extend your thinking: Why do you think the experimental results were different for each trial? 7. Each trial as gas particles had sparse andrandom Each resultdiffered movements which means in some trials there could have been collisions speed decreasing diffusion speed or less temperatures that diffusion On your own: In our lives, we rarely experience increasing are above 373 K (100 °C) or below 273 K (0 °C). Investigate how much diffusion rates differ between these two temperatures. Describe the results of your experiments below. Thees Title hdeah.iq rent at.hff.eu ioan 9o fa98cc tweFTemely if the temperature was extremely hot except the e slowly same goes for particles would move slower Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved Activity B: Get the Gizmo ready: Rates of diffusion ● Click Reset. Introduction: The Diffusion Gizmo allows you to manipulate four more variables: the Wall, the number of x particles in region A, the number of y particles in region B, and the Particle mass. Question: How do factors other than temperature affect the rate of diffusion? 1. Choose a variable: Pick a variable to investigate. Which one did you choose? particles in region A 2. Form hypothesis: How do you think this variable will affect rates of diffusion? If there are lessparticles on side A there will be a faster diffusion time as there is less of a chance lots ofcollisions will occur 3. Set up experiment: In a controlled experiment, only one variable is manipulated, or changed. Set up your experiment so that there is just one difference between set-up A and set-up B. List the Gizmo settings you will use for each set-up below. Set-up A Wall x in A y in B Temp. Particle mass 501 50 300 15 Set-up B Wall x in A y in B Temp. Particle mass 50.1 180 300 15 4. Gather data: Use the Gizmo to fill in each table. As before, the “time to reach equilibrium” is the time it takes for the number of x particles in region A to reach 55% or lower. Set-up A Trial Time to reach equilibrium Set-up B Trial 1 1 2 2 3 3 4 5 111 100 95 4 5 Time to reach equilibrium k 104 90 114 Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved 5. Calculate: Find the average time to reach equilibrium for each experiment: A. Average time to reach equilibrium for set-up A: 98 seconds 107.4 seconds B. Average time to reach equilibrium for set-up B: 6. Draw conclusions: Compare the average times to reach equilibrium for each set-up. A. How did the variable you investigated affect the rate of diffusion? Ifo B. Why do you think this was the case? res's time safifor.am ant that.imremr nsto rieibintoi totInumoiner side 7. On your own: Investigate the remaining variables. Record all experimental results in your notes. Summarize your findings in the space below. *For the scenario you did above, just write “Did Above” Summary of Findings for Variable Wall x particles in A y particles in B Particle Mass A thicker wall slows the rate of diffusion because particles will take longer to pass through smaller openings or barriers. A thinner wall increases the diffusion rate. (Did above variable)- When there are fewer particles in region A, diffusion happens faster because there are fewer collisions and more room for particles to move more freely. When there are more particles, diffusion slows down. If there are many particles in region B, diffusion slows down since the concentration different between A and B is smaller, reducing overall diffusion rate. Heavier particles diffuse more slowly because they move with less speed and energy. Lighter particles diffuse faster since they move more quickly. Reproduction for educational use only. Public sharing or posting prohibited. © 2020 ExploreLearning™ All rights reserved