Posted by Rachel | Posted in Coffee and Accessories | Posted on 05-02-2010
A 50g metal spoon at 20 Celsius is placed in an insulated cup with 200g of coffee at 100 Celsius. ?
1. A 50g metal spoon at 20 Celsius is placed in an insulated cup with 200g of coffee at 100 Celsius. What is the final equilibrium temperature?
2. 25g of 10 Celsius milk is added to 200g of 70 Celsius coffee in an insulated cup. What is the final equilibrium temperature?
3. A 200g aluminum block at 150 Celsius is placed in a large insulated cup with 40g of ice at -10 Celsius. What is the final equilibrium temperature (the ice has completely melted).
_____Heat released = heat gained problems
I’ll do one to show you how:
Let UNITs guide you; always USE THEM in your calculation to prevent errors
Firstly, the eqn: hot Al + cold ice ——> cooler Al and water
heat lost by Al = heat (to warn ice to 0, melt it, and then warm it)
heat lost by Al = (spht Al J/gC * 200 g * (150 – Teq)
heat gained by ice = [(spht ice J/gC * 10C + heat fus J/g + 4.18 J/gC * (Teq - 0)C] * 40 g
Plug and SOLVE for Teq
Basic mathematics is a prerequisite to chemistry – I just try to help you with the methodology of solving the problem.
Use similar methodology for the other
Bodum PAVINA │thermo glass
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