Part 3. Determination of the heat capacity of unknown alloy
14. Select one of two alloys located on the sample bench. Repeat steps 8-13 for the alloy.
Calculations and discussion
1. From the data in Part 1 calculate the calorimeter constant K. Take an average value of both measurements. It’s worth doing this calculation while still in the lap! That way you can tell if your two value of K are close to one another and you can run another trial if they are not.
2. Using this value and data of Part 2 calculate the heat capacity of the unknown metals.
Compare the heat capacity values you obtained with those in the table to identify the unknown metals.
3. As we have seen, the heat capacity of a mixture is determined by the relative masses of the objects. The same can be said for the heat capacity of an alloy, a solid solution of two or more metals. From your experimental value of the heat capacity of the alloy sample the table of heat capacities of pure metals in this handout and a little common sense, you can attempt to identify not only the two metals which go in to the alloy, but also their relative proportion by mass in the sample. Use the data to make your best estimate, and (as always) compare your result to known values.