# Lab Report: Pressure Temperature Volume

Topics: Ideal gas law, Pressure, Gas Pages: 7 (1442 words) Published: October 4, 2012
EXPLORING GAS LAWS-
Astrella Rosano
Lab Partners:Sam Youngdale, Charlie Stalzer, Ni Xhengzhuan. TA: Giang Nguyen
Date Submitted: September 28, 2012
Section: Chemistry 1310-L10
Honor Pledge: I did not copy this work from any others student(s), current students in lab, or old lab reports.

Signature:____________________

Raw Data-
A. Exploring Pressure-Volume Relationships
Pressure (torr)| Volume (mL)|
1384.2| 5|
1198.1| 6|
1038.1| 7|
921.3| 8|
826.2| 9|
752.6| 10|
688.5| 11|
638.5| 12|
593.8| 13|
557.0| 14|
519.9| 15|
492.0| 16|

B. Determining the Ideal Gas Constant

Molar calculations:
Mgs+2HClaq→MgCl2aq+H2(g)
5mL of 3M HCl
nHCl=0.005L×0.3M1L=0.015mol
nHCl 5×excess=0.0155=0.003mol
nMg=0.0032=0.0015mol
mMg=0.0015×24.31=0.0365g

Volumes:
* Tubing:
Inner diameter= 0.53 cm
Length= 46 cm
V=πr2h=π0.265246=10.15mL
* Flask: Measured empirically by filling the flask with water from a measuring cylinder. Volume=132.85mL
* Total:
10.15+132.85=143mL
Pressure of H2:
PH2=Pfinal-Pinitial-PH2O
PH2=364.2-163.6-16.49
PH2=184.11 torr=0.242atm

Pressure vs. Volume
Pressure (torr)| Volume (mL)| Temperature (˚C)|
163.6| | 22.0|
213.5| 0.5| 22.2|
263.3| 1.0| 22.3|
313.2| 1.5| 22.4|
363.0| 2.0| 22.6|
364.0| 3.0| 22.6|
364.1| 4.0| 22.6|
364.2| 5.0| 22.6|

C. Empirical Relationship of Pressure and Temperature

Procedure:
1) Prepare an empty 100mL flask and enclose it with a rubber stopper. 2) Place the flask in a 200mL beaker half-filled with water. 3) Set up the LabQuest instrument, connecting the pressure and temperature probes. 4) Insert the temperature probe into the water and the pressure probe into the flask through the small hope opening in the rubber stopper. 5) Place the whole apparatus on top of a hot plate and start the LabQuest instrument to start measuring the initial temperature and pressure. 6) Begin to turn up the heat of the hot plate, and watch the temperature reading on the LabQuest instrument increase. Ensure that the pressure also increases. 7) Record data onto table.

Tabulated Pressure and Temperature Data
Pressure (torr)| Temperature (˚C)|
747.6| 30|
747.6| 31|
751.8| 32|
762.9| 33|
768.4| 34|
772.2| 35|
776.5| 36|
781.8| 37|
788.3| 38|
789.6| 39|
792.6| 40|
796.4| 41|
799.8| 42|
807.5| 43|
808.7| 44|
809.6| 45|

Processed Data and Graphs:
A. Exploring Pressure-Volume Relationships

Volume vs. Pressure
Volume (mL)| Pressure (torr)|
5| 1384.2|
6| 1198.1|
7| 1038.1|
8| 921.3|
9| 826.2|
10| 752.6|
11| 688.5|
12| 638.5|
13| 593.8|
14| 557.0|
15| 519.9|
16| 492.0|

1/Pressure vs. Volume
1/Pressure (torr-1)| Volume (mL)|
0.000722| 5|
0.000835| 6|
0.000963| 7|
0.001085| 8|
0.001210| 9|
0.001329| 10|
0.001452| 11|
0.001566| 12|
0.001684| 13|
0.001795| 14|
0.001923| 15|
0.002033| 16|

B. Determining the Ideal Gas Constant

pV=nRT
p=184.11 torr=0.242 atm
V=143mL=0.143L
n=0.0015mol
T=22.6˚C=295.6˚K
0.242×0.143=0.0015×R×295.6
R=0.078L atm mol-1K-1
Percentage error:
0.082-0.0780.082=0.0482=4.82%

C. Empirical Relationship of Pressure and Temperature

Pressure (torr)| Temperature (K)|
747.6| 303|
747.6| 304|
751.8| 305|
762.9| 306|
768.4| 307|
772.2| 308|
776.5| 309|
781.8| 310|
788.3| 311|
789.6| 312|
792.6| 313|
796.4| 314|
799.8| 315|
807.5| 316|
808.7| 317|
809.6| 318|

As visible above, the equation for the trend line is: y= 0.2213x + 137.57. This means that the y-intercept of the graph is 137.57. This means that as the pressure decreases to zero, the line could be extrapolated, and the temperature would be ~138 K. This would be considered as the absolute...

References: 1) Bottomley, Leigh, and Lawrence A. Bottomley. Chemistry 1310: General Chemistry Laboratory Manual. Plymouth, MI: Hayden-McNeil, 2013.