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## Homework Statement

1) A 90 g block of unknown metal is heated to 86 degrees C and put in an insulated cup with 175 g water at 23 degrees C. At equilibrium, they are both 25.8 degrees C. What is the specific heat of the metal block?

2) A well insulated cup contains 145 g of ice at 0 degrees C. We pour in 45 g watwer at 75 degrees C.

a- Once equilibrium is established, how many grams of ice remain?

b- What is the final temp in the cup?

## The Attempt at a Solution

1) c ( 90 g) (-60.2 degrees c) + 1 cal/g degrees C) (175 g) (2.8degrees C) = 0

c = 0.0904 cal/g degree C

2)

a- energy available to melt ice: 1 cal/ g Celcius (45 g) ( 75 degrees ) = 3375 cal

energy needed to melt ice: 145 g (80 cal/g) = 11600 cal

not all will melt

80 cal /g (mass melted) = 3375 cal

mass melted = 42.19 g

b- Temp is 0 since there is still ice.