Charles’s Law
Name__________________________
Period______Date________________
Volume-Temperature Data for a Gas Sample (at Constant Mass & Pressure)
In the 1780’s Jacques Charles took volume readings of gases at various temperatures above freezing. He could not
reach temperatures below freezing and “extrapolated” his data to a theoretical “zero point volume”.
Temperature (◦C)
Volume (mL)
100
746
52
650
27
600
10
566
1
548
0
546
Temperature (K)
V/T or k (slope)
Directions: Complete the Temperature column in the table and answer the following questions.
1. Graph the volume versus Kelvin temperature. Extrapolate the graph with a dashed line to where it
crosses the x-axis.
2. Based on the graph, what relationship exists between volume and temperature (direct or inverse)?
3. What characteristic of your graph leads you to this conclusion? ______________________________
4. What is the value of the temperature at the point where the line crosses the x-axis? ___________
5. What is the value of the volume where the line crosses the y-axis? ___________
6. What is the significance of the temperature answer given in question 4? ________________________
7. What happens to the motion of the gas particles at this point? ________________________________
8. From the graph, choose two convenient temperature points (TA and TB). Find the volumes that
correspond to TA and TB from the graph. Draw a dashed line across and down from the graph to each
axis to determine these points. If V varies directly with T, then V = kT (or y = mx + b).
Solving for k (or the slope), we find k = V/T. Using the points selected, calculate the k values by
slope = y2 – y1. Show your work on the graph itself.
x2 – x
V1 V2
V
V
=
because 1 = k & 2 = k
T1 T2
T1
T2
900
Charles’ Law:
The effect of _______________
on the ____________ of a gas.
800
700
Volume (mL)
600
500
400
300
200
Conclusion: As temperature
_______________, volume
_______________
100
0
0
100
200
Temp
(K)
300
400
500