Can Aluminum at 90 Degrees Celsius Melt 10 Grams of Ice?

AI Thread Summary
To determine how many grams of aluminum at 90 degrees Celsius are needed to melt 10 grams of ice at 0 degrees Celsius, first calculate the heat energy required, which is 333.7 kJ for the ice. The specific heat capacity of aluminum is 0.9 J/g°C, and the temperature change (delta T) for aluminum is 90°C to 0°C. Set up the equation to equate the heat lost by aluminum to the heat gained by the ice, ensuring to use the correct latent heat of fusion. The calculations should yield the mass of aluminum needed to achieve the melting of the ice.
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Melting Ice With Aluminum??

Homework Statement



How many grams of aluminum at 90 degrees C would have to be dropped into a hole in a block of ice at 0.0 degrees C to melt 10 g of ice?

Homework Equations



Q = (m)(c)(deltaT)
c of aluminum = 0.9
c of ice = 2.1
c of water = 4.186
333.7 kJ is needed to get past the ice/water boundary

The Attempt at a Solution



I've tried setting up a few different equations, like:
(.01 kg)(2.1)(+45) + (x kg)(0.9)(-45) = 0
(.01 kg)(2.1)(+45) + 333.7 + (x kg)(0.9)(-45) = 0
and a few others I don't have on hand, but I can't seem to get the correct answer. What do I use for delta T? Am I even doing this right at all?

Thanks for your help.
 
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No, I think you are missing it. First calculate the heat energy Q needed to melt 10 g of ice. Your latent heat of fusion should read 333.7 kJ/kg. Then solve for the mass of aluminum having this value of Q, using deltaT=90C (since the final temp of the Al is 0C once it's done its job).
 
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