Energy required to make 2.0 kg of steam

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To create 2.0 kg of steam from 8.0 kg of water at 25 ˚C, a total of 7.1 x 10^6 J of energy must be added. The calculation involves warming the water to 100 ˚C and then converting the water to steam using the specific heat and latent heat of vaporization. The breakdown of energy includes 2,520,000 J to heat the water and 4,600,000 J for the phase change. The solution was confirmed as correct by participants in the discussion. The final energy requirement is thus established at 7.1 x 10^6 J.
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Homework Statement


A container holds 8.0 kg of water at 25 ˚C. How much energy must be added to the water to create 2.0 kg of steam?

Homework Equations


To be honest, not sure. SO MANY equations were given, and I don't know what is a variation of what.

The Attempt at a Solution


Q_total = Q_warm water + Q_boil water
=mc_wt+m_sL_v
= (8.0 kg)(4200 J/(kg* degrees C))(100 degrees C - 25 degrees C)+(2.0 kg)(2.3x10^6)
=2520000 J + 4600000 J
=7120000 J
=7.1 x 10^6 J

Therefore 7.1 x 10^6 J of heat energy have to be added to the water to create 2.0 kg of steam.

Does that make any sense?
 
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LonelyElectron said:
Does that make any sense?
Yes, it makes a lot of sense.
 
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kuruman said:
Yes, it makes a lot of sense.

Okay perfect! So its correct? You guys are the best. I hope you know how much your help is appreciated!
 
LonelyElectron said:
So its correct?
Yes, it's correct.
 
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