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1. The problem statement, all variables and given/known data

How much heat will be lost when 120 g of steam at 100°C is condensed to water at 80°C?

2. Relevant equations

Q = mc∆t

Q = m LV

3. The attempt at a solution

Q = mc∆t

Q = 0.12 x 4186 x (80 – 100)

Q = 10046.4 J

Q = m LV

Q = 0.12 x (- 2.3 x 106)

Q = 276000 J

= 10046.4 + 276000 = 286046.4

= -2.9 x 105 J

Is the latent heat of condensation negative to that of vaporization?

Question #2

1. The problem statement, all variables and given/known data

If 20 g of ice at 0° is added to 180 g of water at 22°C, what will the final temperature of the water be?

2. Relevant equations

Q = mc∆t

3. The attempt at a solution

mc∆t = mc∆t

0.02 x 2050 (0-T) = 0.18 x 4186 (T-22)

-41T = 753.48T - 16576.56

-794.48T = -16576.56

-794.48T/-794.48 = -16576.56/-794.48

T = 20.86

For this question, is the latent heat of fusion needed?

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# Homework Help: How much heat will be lost

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