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Jayhawk1
Apr25-05, 12:52 AM
Here's the problem:

The density of water at 4oC is 1.00x103kg/m3. What is the change in density if the water is heated to 85oC? Remember that the change will be the final density minus the initial density. Assume a coefficient of volume expansion of 2.10x10-6/oC.

Now, I have tried using a standard mass of 1000KG and solving the problem that way, however I am way off... please help

xanthym
Apr25-05, 01:33 AM
Here's the problem:

The density of water at 4oC is 1.00x103kg/m3. What is the change in density if the water is heated to 85oC? Remember that the change will be the final density minus the initial density. Assume a coefficient of volume expansion of 2.10x10-6/oC.

Now, I have tried using a standard mass of 1000KG and solving the problem that way, however I am way off... please help
SOLUTION HINTS:
By definition:
{Coefficient of Volume Thermal Expansion} = α = (-1/ρ)(Δρ/ΔT)
::: ⇒ Δρ = -αρΔT
Use values given in problem statement for terms on the right to calculate "Δρ".


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OlderDan
Apr25-05, 01:35 AM
Here's the problem:

The density of water at 4oC is 1.00x103kg/m3. What is the change in density if the water is heated to 85oC? Remember that the change will be the final density minus the initial density. Assume a coefficient of volume expansion of 2.10x10-6/oC.

Now, I have tried using a standard mass of 1000KG and solving the problem that way, however I am way off... please help

Calculate the volume expansion assuming an initial volume V_0. Add that to the initial volume to find a final volume. Multiply the initial density times V_0 to get an initial mass expressed in terms of V_0. Divide that mass by the new volume. The V_0 factors will all divide out. It will work.