Concept explainers
Use the heat equation to calculate the energy for each of the following (see
TABLE3.11):
a. calories lost when 85 g of water cools from 45 °C to 25 °C
b. joules to heat 75 g of water from 22 °C to 66 °C
c. kilocalories to heat 5.0 kg of water from 22 °C to 28 °C
d. kilojoules to heat 224 g of gold from 18 °C to 185 °C
TABLE 3.11 Specific Heats for Some Substance
Substance |
|
|
Elements | ||
Aluminum, Al(s) | 0.214 | 0.897 |
Copper, Cu(s) | 0.0920 | 0.385 |
Gold, Au(s) | 0.0308 | 0.129 |
Iron, Fe(s) | 0.108 | 0.452 |
Silver, Ag(s) | 0.0562 | 0.235 |
Titanium, Ti(s) | 0.125 | 0.523 |
Compounds | ||
Ammonia, NH3(g) | 0.488 | 2.04 |
Ethanol, C2H6O(?) | 0.588 | 2.46 |
Sodium chloride, NaCl(s) | 0.207 | 0.864 |
Water, H2O(?) | 1.00 | 4.184 |
Water, H2O(s) | 0.485 | 2.03 |
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CHEMISTRY:INTRO.GEN ORG.W/MODIFIED MAS
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