First law of thermodynamics and work done

AI Thread Summary
To find the work done when converting two kilograms of water at 100°C to steam at 1 ATM, the pressure remains constant, allowing the use of the formula W = PΔV. The density of steam at this temperature is 0.598 kg/m³, which helps calculate the change in volume. The integration method is not necessary; instead, simply apply the pressure and volume change directly. The correct answer options range from 2.1 x 10^4 to 3.4 x 10^5 J. Understanding the relationship between pressure, volume, and work is crucial for solving this problem accurately.
fly_bo1
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Two kilograms of water at 100oC is converted to steam at 1 ATM. Find the work done (in J). (The density of steam at 100oC is 0.598 kg/m3.)

a. 4.6 x 104
b. 3.4 x 104
c. 1.2 x 105
d. 2.1 x 104
e. 3.4 x 105

I'ved use the integration holding volume as a variable. However, I don't know why I am not getting the right answer.
 
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fly_bo1 said:
Two kilograms of water at 100oC is converted to steam at 1 ATM. Find the work done (in J). (The density of steam at 100oC is 0.598 kg/m3.)

a. 4.6 x 104
b. 3.4 x 104
c. 1.2 x 105
d. 2.1 x 104
e. 3.4 x 105

I'ved use the integration holding volume as a variable. However, I don't know why I am not getting the right answer.
You don't have to do an integration. Assume that the change in volume from water to steam occurs at 1 Atm external pressure and that the steam is created gradually. Pressure is constant, so W = \int PdV = PV (assume initial volume is 0).

AM

PS Welcome to PF, btw.
 
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