Kelvin, Celsius, Fahrenheit Kelvin, Celsius, Fahrenheit Transfer of thermal energy from one object to another; goes from hot to cold
Second; particles are moving faster so they have more KE Average kinetic energy of particles in an object due to their random motion faster Kinetic energy temperature Second; particles are moving faster so they have more KE
Increase in temperature increases faster Farther apart Thermal expansion Increase in the volume Increase in temperature increases faster Farther apart As temperature changes, expands and contracts Less cracks if in different segments
SI unit for temperature is _____________. Other scales are _____________ and ____________. Kelvin Celsius Fahrenheit
8. Specific heat heat temperature 1g 1 ° lower less metals low high
Q = m c ΔT ΔT = Tf-Ti 0.2kg 4,184 Specific heat heat mass Temp change Q =0.2x4184x55 =46024 Q =46,024 J ΔT= 80-25 = 55 Q = ?
(watch your signs– don’t worry too much about units) Q = 3780 J 100 9 4.2 Q = -1.07 J /g°C -3780 (watch your signs– don’t worry too much about units) 55 65
calorimeter Thermal energy lost absorbed 910 c = 0.14 J/g°C 50 130 ΔT = 211°C 2637.5 ΔT = 211°C = Tf – Ti 25 0.50 ΔT = 211°C = Tf – 25 Tf = 236°C
Practice on pages 12-13 We will finish the notes afterward!
conduction
Convection liquid gas
Energy is always conserved. Radiation electromagnetic Energy is always conserved. Thermal energy flows from cold to hot ONLY when work is done. Absolute zero cannot be reached.
Give an example of conduction. How do we use convection? What is radiation? Is it always harmful?
Heating curve - WATER condensation vapor 100˚C - evaporation liquid melting 0˚C - freezing solid