Substance
ID: 691007 • Letter: S
Question
a. You are given an unknown substance. In the lab, you determinethe specific
heat of thesubstance.
You use the followingdata: mass of theunknown = 9.75 x 10 – 2 kg
calories absorbed by the unknown = 537 cal
beginning temp. of unknown = 76°F
end temp. of unknown =250°F.
From the table below, determine the identity of the unknownsubstance.
Specific Heat Capacity (cal/g x°C)
Copper
0.092
Iron
0.11
Aluminum
0.21
Silver
0.057
Lead
0.031
Specific Heat Capacity (cal/g x°C)
Copper
0.092
Iron
0.11
Aluminum
0.21
Silver
0.057
Lead
0.031
Explanation / Answer
You would use the equation Q= mc T. You can solve for c (specific heat) which would give you c= Q/(mT). Q is calories absorbed, m is your mass, and the change is temperature is the final minus initial. Your answer for c should match one of the specific heats given in the chart.