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**1. Homework Statement**

A Pyrex container is filled to the very top with 40.0L of water. Both the container and the water are at a temperature of 90.0 degrees C. When the temperature has cooled to 20.0 degrees C how much additional water can be added to the container?

**2. Homework Equations**

(delta-V)/(V-initial)=(beta)(delta-T)

(delta-L)/(L-initial)=(alpha)(delta-T)

(delta-A)/(A-initial)=2(alpha)(delta-T)

**3. The Attempt at a Solution**

The change in the volume of water:

(delta-V)=(beta-water)(delta-T)(V-initial)=(207*10^-6/K)(70K)(40L)=0.5796L

the final volume of water- 39.4204 L

change in holding capacity of Pyrex container:

I used the equation for change in linear direction for the height of the cylinder and change in the area for the cross-sectional area of the cylinder.

(delta-L)=(alpha-Pyrex)(delta-T)(L-initial)=(3.25*10^6/K)(70K)(L-intial)

final length=.9997725(L-initial)

(delta-A)=2(alpha)(delta-T)(A-initial)=2(3.25*10^6/K)(70K)(A-initial)

final area=.999545(A-initial)

final volume of cylinder=final length*final area=.9993176(V-initial)=.9993176(40L)=39.9727 L

final volume of cyliner-final volume of water=0.5523L

Does my method make sense?