Specific Heat Capacity Problems

1. Specific Heat Capacity Problems

2. If 3940 J of energy is added to 8071 grams of tungsten at -8.0 °C, what will the final temperature be? • sW = 0.134 J/g°C 3940 J = 0.134 J/g°C x 8071 g x (Tf- 8.0°C) 3940 J = (Tf- 8.0°C) 1081.5 J/°C Tf= 12°C

3. 15,137 grams of sodium chloride is heated from 35 oC to 68 oC, how much heat was added? sNaCl = 0.85 J/g°C Q = 0.85 J/g°C x 15,137 g x (68°C – 35°C) Q = 424,592 J or 4.2 x 103 kJ

4. If 3.87 kJ of heat is added to silver at 21 oC and it heats to 74oC, how many grams were present? sAg= 0.24 J/g°C 3,870 J = 0.24 J/g°C x m x (74oC-21 oC) 3,870 J = m 12.72 J/g m =304 g or 3.0 x 102 g

5. A certain substance heats from -35°Cto -11 °C when 39.5 kJ of energy is added to 811 grams. What may this substance be? 39,500 J = sunk x 811 g x (-11°C-(-35°C)) sunk = 39,500 J 19,464 g°C = 2.03 J/g°C Solid water or ice!

6. If 6390 J of energy is added to 69 g of water at 3oC, what will the final temperature be? • sH2O= 4.184 J/g°C • 6390 J = 4.184 J/g°C x 69 gx (Tf- 3oC) 6390 J = Tf - 3oC 288 J/oC 22 oC = Tf - 3oC Tf = 25 oC

7. If 23 kJ of energy is added to 87 g of iron at 7oC, what will the final temperature be? • sFe = 0.45 J/g°C 23,000 J = 0.45 J/g°C x 87 g x (Tf-7oC) 23,000 J= Tf-7oC 39 J/oC 587 oC= Tf-7oC Tf= 594 oC