WebQuest: Solids, Liquids, and Gases, chemistry homework help

WebQuest: Solids, Liquids, and Gases In this WebQuest, you will use the States of Matter interactive to explore similarities and differences among the particle motion of solids, liquids and gases. Part I: How do particle arrangements and motions differ for solids, liquids, and gases?

For this interactive, make sure that the “Solid, Li quid, Gas” tab appears in the top left corner of the screen. The cylinder represents a container with a fixed volume that can be filled with different types of gas particles. Select “Oxygen” from the list of molecules and click the “Gas” button to display an animation of oxygen molecules in the gas phase. Your screen should look similar to the screen below.

1. How does the animation illustrate core ideas of t he kinetic molecular theory? Justify your response. 2. The particles in the oxygen gas animation show many different kinds of motions. Identify three different kinds of motions/interactions you observe. Which motions create pressure on t he walls of the container?

3. Click the “Liquid” and then the “Solid” buttons for oxygen and study the particle motion for each phase.

Compare the particle motions for each phase by completing the chart below:

Gas Liquid Solid level of order observed in particle arrangements average distance between particles main types of molecular motion how well the particles fill the container temperature reading displayed distribution of particle speeds Part II: How can two substances be the same temperature and yet exist in different phases?

Select “Argon” molecules and “Gas” phase to see an animation of gas phase argon atoms.

4. What temperature measurement (value and units) does the thermometer show? 5. What is the freezing point of water in Kelvin and Celsius degrees? 6. Room temperature is about 22 degrees Celsius or 72 degrees Fahrenheit. How many Kelvin is this?

7. Use the slider under the cylinder to increase t he temperature to 292 Kelvin. Characterize the motions of the argon atoms at that temperature:

Select “Water” molecules and “Liquid” phase to see water molecules at 292 Kelvin. 8. How do the motions and average distances between water molecules at 292 Kelvin compare to the motions and average distances between argon atoms at the same temperature?

9. How do the type and strength of intermolecular forces among argon atoms compare to the type and strength of intermolecular forces among wate r molecules? How does this explain the observed differences in the particle-level animations for argon and water at 292 Kelvin?

Part III: How does adding or removing heat change particle motions of a substance?

Select “Neon” molecules and the “Solid” phase. Use the slider under the cylinder to increase the temperature in 20-Kelvin increments. Record your observations at each temperature by completing the table:

Thermometer reading Description of neon atom movement 9 K 29 K 49 K 10. Which statement best describes the changes in pa rticle motion that occur when heat is gradually removed from a substance? Use the interactive to explore this phenomenon if you are unsure. Select the checkbox next to your answer.

A. All particles speed up and move with the same speed.

B. Some particles speed up, but there is still a range of particle speeds.

C. Some particles slow down and fewer particles collide with the walls of the container.

D. All particles slow down, to the point where all particles vibrate with identical frequencies.