p19_036.pdf

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Chapter 19 - 19.36

36. (a) Using Eq. 19-17, the heat transferred to the water is

Q w = c w m w ∆ T + L V m s

=(1a / g

·

C ◦ )(220g)(100 ◦ C

−

20 . 0 ◦ C)+(539cal / g)(5 . 00g)

=20 . 3kcal .

(b) The heat transferred to the bowl is

Q b = c b m b ∆ T =(0 . 0923cal / g

·

C ◦ )(150g)(100 ◦ C

−

20 . 0 ◦ C)=1 . 11 kcal .

(c) If the original temperature of the cylinder be T i ,then Q w + Q b = c c m c ( T i −

T f ), which leads to

T i = Q w + Q b

c c m c

+ T f =

20 . 3kcal+1 . 11kcal

(0 . 0923cal / g

·

C ◦ )(300g) +100 ◦ C= 873 ◦ C .