## Essential University Physics: Volume 1 (3rd Edition)

$160J/K$
We know that the change in temperature has to do with the masses and the specific heats of the substances. Thus, we find that the final temperature is: $T_f=288+(140)(\frac{2.4}{3.5})(\frac{.87}{4.184})=308K$ Now, we find the total change in entropy: $\Delta S = (3.5)(4184)(ln(\frac{308}{288}))+2.4(.87)(ln(\frac{308}{428}))\approx 160J/K$