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May 6, 2016

# Homework Help: Jake

Posted by Chemistry on Tuesday, October 16, 2007 at 6:52pm.

A combustion bomb containing 5.417 g of aluminum metal and 15.974 g of iron III oxide is placed in an ice calorimeter that initially contained 7.746 kg of ice (at o degrees C) and 7.894 kg of liquid water (at o degrees C). The reaction, once ignited by remote control, forms pure iron and aluminum oxide. It is observed that the calorimeter contains 7.493 kg of ice and 8.147 kg of liquid water after the reaction. The heat of fusion of ice is 335 J/g. What is the enthalpy change for this reaction per mole of iron formed?

So far I have:

Al(s) + Fe2O3 (s) ----> AlO3 + 2Fe

am i supposed to include the ice and water in the balanced equation? what should i do next, i'm sort of lost.
• Jake - bobpursley, Tuesday, October 16, 2007 at 8:07pm

The ice melting tells you the amount of heat released.
How much heat does it take to melt 7.893-7.393 kg of ice.

Then, having the energy, you can determine enthalpy based on the moles of iron formed. The reaction is a little tricky to figure moles of iron, you have to determine which is the limiting reactant.