Warm Up 1-20-16

1. What do we use to measure temperature?

2. What is the difference between heat and temperature?

3. True or false: Heat is energy and energy is heat. Explain your answer.

AgendaTurn in HW-specific heat WSNotes Unit 6-3Virtual Lab calorimeter

HomeworkJan 29- Online HW

Answers:1. Specific heat2. O Kelvin3. Endothermic4. Exothermic5. 4.186. Delta T7. O oCelcius8. 0.4169. 63,536 Joules10. 7.974 g11. 0.2 12. 13,794 joules13. 0.031

Answers:14. 27, 912 joules15. 58,050 joules16. 12.096 grams17. 15.01818 Celsius18. Object B, lower specific heat means it requires less heat for temperature to increase

EnthalpyUnit 6 - 3

Enthalpy• Enthalpy – the total quantity of

heat in a reaction• Changes in enthalpy are measured

through indicators (temperature)• Represented by ΔH

Enthalpy Change• The sign of H indicates the

direction of heat transfer.

+H indicates heat is entering the system (endothermic)

- H indicates heat has left the system (exothermic).

Enthalpy Change• For reactions H = H (products) – H (reactants).

Example:• 2H2 (g) + O2 (g) 2H2O(g) H = -

483.6kJ

Molar Heat Capacity • The quantity of heat required to

raise the temperature of one MOLE of a substance by one degree Celsius or Kelvin

Molar Heat Calculation

• Q = n x ΔT x Cp

n = molesCp = molar heat capacity

Example Problem• The molar heat capacity of CCl4 is

130.7 J/mol·C. What is the enthalpy change when 125g of CCl4 is heated from 10 °C to 32 °C.

Convert to mole if given grams

Calorimeter• An instrument for measuring the

heat of a reaction during a chemical process

$13,000 – $40,000

Specific Heat LabQ gained by water =Q lost from the metal

Assignments• Summary• Virtual calorimeter lab

http://www.wiley.com/college/trefil/0470118547/vdl/lab_calorimeter/

Homeroom 1-20-16 -AP classes overview-Reflections and setting goals-Quote of the week

Homeroom 1-20-16 On a piece of line paper. Answer the following questions in complete sentences.1.What were the high point(s) and low point(s) of last year?2.List three things your did successfully in school or outside of school.3.List several goals you want to achieve this semester