Science Homework Help

Experiment 22 in lab manual

Absolute Zero of Temperature

Objective: To determine the absolute zero of temperature by examining the pressure-temperature relationship of a gas at constant volume and constant mass by:

a. Linear Extrapolation

b. Mathematical Calculation

Equipment: Device with Internet connection, calculator, Word and Excel software

For further information: Absolute Zero of Temperature Background:

Absolute Zero #1

https://www.encyclopedia.com/science-and-technolog…

Absolute Zero #2

Simulation: Absolute Zero Simulation

https://phet.colorado.edu/sims/html/gas-properties…

A. Complete the 8Pre-lab questions

B. Complete the main assignment by using the simulation to generate3 sets of data,

produce 1 graph with three linear regressions,determineabsolute zero and the % error of each regression..

C. Complete the 4 Post-lab questions

D. Conclusion

Important equation:

Experimental value: PV = nRT.

where P = Pressure

V = Volume

T = Temperature

n = number of moles

R = Universal gas constant

Theoretical value for Absolute Zero: –273.15 (°C)

Activity	Lab#11 Rubric	Total Score 100
Pre-lab questions		16 pts
	Simulation	15 pts
Experiment Activity	Data chart / Graph	25 pts
	Calculations / % error	15 pts
		55 pts
Post-lab questions		16 pts
Conclusion		13 pts

Appendix A

Appendix B : Sample trial data chart

Run A	Tempera– ture (°C)	Pressure (ATM)		Run B	Tempera– ture (°C)	Pressure (ATM)		Run C	Tempera– ture (°C)	Pressure (ATM)
Boiling water	100	21.6				35.4				76.2
Atmosphere	26	17.5				28.6				60.9
Ice	0	15.9				26.1				55.5
Dry ice & Ethanol	-72	11.8				19.3				40.9
Liquid Nitrogen	-196	4.4				7.4				15.8

Data Chart: Do not use as data for pressure.

Appendix C

How to write a conclusion: ¼ page

1.Purpose restated

2. Did you meet the objective(s)? Why or why not?

Refer to graph or data table. State % error as

evidence–Lower than 5% is a successful expt.

3. Suggestions to improve the possible errors.

4. Suggestions to enhance the lab.

5. Suggestions to extend the lab.

Name _____________________________________ Lab Section ________Date________________

Pre–laboratory Assignment: Experiment 11

Determination of Absolute Zero

All numerical answers should be given to the correct number of significant digits. (Submit your answers on separate sheets as necessary.)

1. What is Gay-Lussac’s Law?

2. What is the temperature of the alcohol/dry ice slurry? What precaution(s) should be taken in working with the slurry?

3. What is the boiling point of liquid nitrogen? What precaution(s) should be taken in working with liquid nitrogen?

4. Why must the gas container be submerged slowly when you place it in liquid nitrogen?

5. What is the definition of temperature as it pertains to the motion of gas particles?

6. The equation of a line is given by the function y = mx + b. Determine the value of the x-intercept (where y = 0) of the line defined by the equation y = 3x + 9. Using the equation for a straight line, what is the formula for the x intercept?

7. What effect will a 1.0°C error (all temperature readings are 1.0°C greater than the actual value) in determining absolute 0 K? Justify your answer.

8. What effect will a 0.10 atm error (reading is 0.10 atm. greater than the actual value) greater than the actual value) have in determining absolute 0 K? Justify your answer.

How to produce data using the simulation:

Three runs will be conducted. Threelinear lines will be produced on one graph.

1) Set the temperature for boiling water. Record the temperature (ºC) and the pressure (atm) in the chart for run A.

2) Set the temperature for the atmospheric temperature. Record the temperature (ºC) and the pressure (atm) in the chart for run A.

3) Set the temperature for solid ice. Record the temperature (ºC) and the pressure (atm) in the chart for run A.

4) Set the temperature for slurry mixture of dry ice and ethanol (See lab manual). Record the temperature (ºC) and the pressure (atm) in the chart for run A.

5)Set the temperature for liquid nitrogen (See lab manual). Record the temperature (ºC) and the pressure (atm) in the chart for run A.

Increase the amount of molecules in the container.

6) Repeat 1-5 for Run #2.

Increase the amount of molecules in the containeronce more.

7) Repeat 1-5 for Run #3.

CALCULATIONS

Show all calculations for full credit. Answers should be given to the correct number of significant

digits.

1.Using MS Excel , plot the graph of Pressure (on the vertical axis) vs. Temperature on

the horizontal axis for the set of points and find the curve of best fit and determine the equation of the curve of best fit.

2.Use the curve of best fit to determine the experimental value of the absolute zero of temperature.

3.Calculate and determine the absolute zero temperature in (ºC).

4. Calculate the percent difference between each of the threeexperimental values and the theoretical value of absolute value.

Post Lab Questions:

1. Are your graphs linear? If so, why? If not why?

1. Give reasons why your values of absolute zero do not agree with the theoretical value.

2. How did the increase in mass affect the absolute value? (refer to Procedure 8)

3. Describe the results of the balloon and liquid nitrogen. Give reasons for these results.

4. Where during your experimental set up do you expect to find sources of error?

Absolute Zero

Run A	Tempera– ture (°C)	Pressure (ATM)		Run B	Tempera– ture (°C)	Pressure (ATM)		Run C	Tempera– ture (°C)	Pressure (ATM)
Boiling water
Atmosphere
Ice
Dry ice & Ethanol
Liquid Nitrogen

Data Chart:

Data

Temperature (°C)	Pressure (atm) Run A	Pressure (atm) Run B	Pressure (atm) Run C
100
26
0
-72
-196