- #1

irishbob

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## Homework Statement

A 50.0g copper calorimeter contains 250 g of water at 20 C. how much steam must be condensed into the water if the final temperature of the system is to reach 50 C?

## Homework Equations

Q=-mLv where Q is heat energy, m is mass, Lv is latent vaporization constant of water (3.33x10^5 J/kg).

and

Q=mc(Tf-Ti) where Q is heat energy, m is mass, c is specific heat (steam is 0.48 cal/(gC) or 2010 J/(kgC)), and Tf-Ti is delta T.

## The Attempt at a Solution

100 C steam -> 100 C water -> 50 C water and Cu

Qwcu=mc(delta)T=0.05kg(387 J/kgC)(50-20)C+0.25kg(4186 J/kgC)(50-20)C=32000 J

32000J=-mLv=-m(2.26x10^6)

|-m|=14.16g

What am I doing wrong?