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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. How many kJ of energy was released by 401g of water if the temperature dropped from 65.3°C to 13.9°C?
2. What is the specific heat capacity of a substance ( in J/(g-°C) if 46.1g of the substance released 4.35 kJ of energy while the temperature went from 67.1°C to 12.0°C?
3. A container of oil gained 6.87 kcal of energy and the temperature went from 32.1°C to 54.8°C. How many grams of oil is there? Assume specific heat capacity of the oil is 0.913cal/(g-°C).
4. What is the change in temperature (ΔT) of 532g of water if it released 22.9 kcal of energy.
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)?
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