Learning Objectives:

Upon completion of this experiment, students will:

• 1. (CLO1). Explain basic chemical concepts related to chemical changes, energy, and properties of matter.  

  2. (CLO3).  Analyze evidence to decide if generalizations or conclusions based on the obtained data are warranted

  3. (CLO4).  Interpret and utilize mathematical formulas while solving problems

  4. (MLO)  Use the Gas laws, combined gas and ideal gas equations to perform calculations to determine pressure, volume or temperature for a given gas using values at standard temperature and standard pressure of gases.

  5. Use Graphical analysis to determine the relationship between the above variables.

 The temperature is a measure of the heat, the motion of the particles or the kinetic energy of the molecules.   According to the Kinetic Molecular Theory, temperature also affects the kinetic energy of the particles.  As the temperature increases, the particles speed up becoming more energetic, which means the kinetic energy increases.  If the temperature decreases, the particles lose energy, slowing down. If the particles become cold enough, they can lose all energy and all motion stops.  At this point, the matter has reached absolute zero (zero Kelvin).   

Lastly, Pressure is dependent upon how often the particles hit the surface and the force exerted by the particles as they collide with the surface of the container.  If there are many collisions with the surface of the container, the pressure will be greater and if the collisions are more forceful because the molecules are moving with greater speed, having greater energy, the pressure will be greater.  So both the amount of the substance present and the temperature of the matter will affect the pressure. The kinetic molecular theory states the particles in an ideal gas do not have attractive or repulsive forces between particles. If strong intermolecular forces exist between particles, then the pressure of the gas can be affected.  

The gas laws compare any two of the above variables and try to understand how one variable is affected by the other.  There are several gas laws. Boyle’s Law is the relationship between Pressure and Volume:  VP = kb (a constant value when temperature and amount are constant) or volume is proportional to the inverse pressure 1/P.  Boyle’s Law can also be written P1V1 = P2V2. The data from determining the pressure at various volumes can then be graphed and the resulting relationship can determine if volume and pressure are directly or indirectly proportional.

Charles’ Law is the relationship between Volume and Temperature: V= kcT or Volume is proportional to Temperature.  Charles’ Law can be written
V1/T1 =V2/T2.   In a graph, where Temperature is the independent variable, x, and Volume is the dependent variable, y, the data should be linear.  Extrapolation of the graph to the x intercept or where the volume is zero, the temperature should theoretically be 0 Kelvin or absolute zero.   

There are other gas laws, but this assignment is to show the relationships between volume and pressure and volume and temperature.  

You can use the following simulations to explore the topics below.   

Simulation:   https://teachchemistry.org/classroom-resources/the-gas-laws-simulation

Description

In this simulation, students will investigate three of the fundamental gas laws, including Boyle’s Law, Charles’ Law and Gay-Lussac’s Law. Students will have the opportunity to visually examine the effect of changing the associated variables of pressure, volume, or temperature in each situation. Also, students will analyze the gas samples at the particle level as well as manipulate quantitative data in each scenario. Finally students will interpret trends in the data by examining the graph associated with each of the gas laws. 

Simulation:   https://phet.colorado.edu/en/simulation/gases-intro 

Topics

• • Ideal Gas Law

  • Pressure

  • Volume

  • Temperature

Description

Pump gas molecules to a box and see what happens as you change the volume, add or remove heat, and more. Measure the temperature and pressure, and discover how the properties of the gas vary in relation to each other.

Sample Learning Goals

• • Describe the behavior of the gas particles in the box.

  • Identify the relationship between pressure, volume, temperature, and number of gas molecules.

  • Describe the relationship between particle-wall collisions and pressure.

  • Predict how changing temperature will affect the speed of molecules.

Pre Writing assignment

There is no required pre laboratory writing assignment. 

Procedure and Report

The Laboratory report of the assignment contains questions, data collection, calculation and reporting of results. 

We will test the validity of Boyle’s Law that says Volume is directly proportional to inverse pressure.   This means that as the volume increases, the pressure decreases or as volume decreases, pressure increases.    We will use a syringe that is connected to a pressure sensor.   We could use a manometer to measure pressure, but it is difficult to change the volume with this type of tool.  So we will use a pressure sensor connected to the MicroLab interface and a computer 

 Part B:  Charles’ Law - 

    Determination of volume dependence on temperature  and an Estimation of Absolute Zero

Post Laboratory Problems and Conclusion paragraph

There are no post laboratory problems or conclusion paragraph for this laboratory assignment.