Question 396Steam Plants - Assistant Engineer
70% to passIf a boiler generates saturated steam at 125.3 psig, how much heat is required to change the water into steam if the feed water temperature is 240°F? Illustration SG-0004

A30.5 Btu/lb
B116.5 Btu/lb
C582.7 Btu/lb
D983.4 Btu/lb
AI Explanation
The correct answer is D) 983.4 Btu/lb. To change water into saturated steam at 125.3 psig, the heat required is the latent heat of vaporization at that pressure, which is 983.4 Btu/lb. This value can be found in steam tables or other references for thermodynamic properties of steam. The other answer choices are incorrect because they do not represent the full latent heat of vaporization required to change the water at 240°F into saturated steam at 125.3 psig. Options A, B, and C represent only partial amounts of the total heat required for this phase change.
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