1. Lecture 284/11/07 St. Luke's Society Wednesday April 11th at 7pm

2. Thermodynamics: study of energy and transformations Energy Kinetic energy Potential Energy

3. Units 1 calorie (cal) 1 calorie (cal) = 4.184 Joule (J) Calorie (Cal)

4. 1 st Law of Thermodynamics Law of conservation of energy Energy in the universe is conserved System vs. surroundings vs. universe Internal energy

5. Specific heat capacity (C) Quantity of energy to increase the temperature of 1 gram of a substance by 1 degree C (liquid water)= 4.184 J/g·K C (ice)= 2.06 J/g·K C (steam)= 1.84 J/g·K C (aluminum)= 0.902 J/g·K Molar heat capacity Quantity of energy that must be transferred to increase the temperature of 1 mole of a substance by 1 °C

6. Specific heat capacity (C) q = Cm∆T

7. Heat transfer q gained + q lost = 0 q gained = - q lost 55.0 g of iron at 99.8°C is plunged into 225 g of water at 21°C. What is the final temperature? C (iron) = 0.451 J/g-K

8. How much energy has a cup of coffee lost after it has cooled down to room temperature?

9. Does drinking ice water cause you to lose weight? Does drinking ice cold coke?