Heat Calculation Handout 3

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Removed: 1,17d0

Complete these questions after going over Special Case of Initial/final Temp Calculations

5. What is the initial temperature of a 32.1g sample that absorbed 12.4kcal of energy and has a final temperature 726°C? The specific heat capacity of the sample was 0.651cal/(g-°C).

6. What is the final temperature of a 521g of water that loses 1.5kJ of energy and has an initial temperature of 87.4°C and a specific heat capacity of 3.21 cal/(g-°C)?

Removed: 19,20d1

Answers:1) 86.2 kJ 2) 1.71J/(g-°C) 3) 331g 4) -43.0°C 5) 133°C 6) 87.2°C

Please do the following problems on 2 separate sheets of paper (no more than 3 problems per side of paper)

Answer the following problems showing all work (look at Example of Work Handout) (Note: 1.00cal = 4.18J)

1. A container of oil was given 2.35Kcal of energy and its temperature raise from 34.9°C to 102.4°C. If the specific heat capacity of oil is 1.75 J/(g-°C), how many grams of oil are you heating?

2. A 256.g sample of water loses 15.3 kcals of energy. If the initial temperature of the water was 98.3°C, what is the final temperature?

3. How many kcals of energy was released by 625g of water if the temperature dropped from 87.2°C to 19.6°C?

4. What is the initial temperature of a 11.4g sample that absorbed 6.2kcal of energy and has a final temperature 726°C? The specific heat capacity of the sample was 0.97cal/(g-°C).

5. What is the specific heat capacity of a substance if the 92.1g of substance released 2.10 kcal of energy while the temperature went from 76.3°C to 21.0°C?

6. How much energy in kcal is lost by 521g of water that drops its temperature from 64.3°C to 13.7°C?

7. What is the final temperature of a 43.1g of oil that loses 4.2kJ of energy and has an initial temperature of 124°C and a specific heat capacity of 3.21 cal/(g-°C)?

8. A container of water released 687cal of energy and the temperature went from 54.2°C to 31.5°C. How many grams of water is there?

9. What is the initial temperature of 32.1g sample that released 421 cals of energy and has a final temperature of 10.2°C. The specific heat capacity of the sample is 5.21 J/(g-°C).

Answers:1) 83.2g 2) 38.5°C 3) -42.3 kcal 4) 165°C 5) 0.412cal/(g-°C) 6) -26.4kcal 7) 117°C 8) 30.3g 9) 20.7°C