Warm Up #2 In an endothermic reaction, if 350 J of heat is absorbed, how much heat is lost by the surroundings? How do you know? If the final temperature.

Slides:

Advertisements

Similar presentations

Thermochemistry.

Advertisements

 MOLAR HEAT: it is the enthalpy changes(ΔH) for 1 mole of substance to change a state.  Molar Heat of Fusion (ΔH fus ): the amount of heat absorbed.

Aim: How to measure energy absorbed during a phase change

Calculations in Chapter 10. Molar Enthalpy of Fusion Used when melting or freezing = ___energy ____ mol of substance Can be arranged to find any of the.

Calorimetry AP Chemistry.

Calorimetry How to use math to describe the movement of heat energy Temperature Change Problems Temperature Change Problems Phase Change Problems Phase.

Energy Transformations Thermochemistry is the study of energy changes that occur during chemical reactions and changes in state. The energy stored in the.

Thermo- Chemistry Heat Transfer Thermo Equations Phase changes F.

Calorimetry How to use math to describe the movement of heat energy Temperature Change Problems Temperature Change Problems Phase Change Problems Phase.

THERMOCHEMISTRY: HEAT and CHANGE. When a material is heated (or cooled), it can undergo one of these changes: Its temperature changes OR Its physical.

1  H = H final - H initial If H final > H initial then  H is positive Process is ENDOTHERMIC If H final > H initial then  H is positive Process is ENDOTHERMIC.

Molar Enthalpy of Vaporization

Phase Changes and Thermochemistry

Good Morning 11/16/2015 Today we will be working on the notes for ch 11.

Thermochemical Calculations

Unit 13 Thermochemistry. Energy u The ability to do work or cause a change u Often measured in joules (J) u Law of Conservation of Energy – energy is.

Aim: How to measure energy absorbed during a phase change DO NOW: 1. A g piece of iron absorbs joules of heat energy, and its temperature.

1 OBJECTIVES: –Classify, by type, the heat changes that occur during melting, freezing, boiling, and condensing. –Calculate heat changes that occur during.

Unit 13 Thermochemistry.

Thermo-chemistry.

Chemistry 17.3.

Thermochemistry.

PHASE CHANGES Each state of matter is called a PHASE

Chapter 16: Energy and Chemical Change

ENTHALPY DH = Hfinal - Hinitial Process is ENDOTHERMIC

Ch. 17 THERMOCHEMISTRY 1.

Chapter 17 Thermochemistry 17.3 Heat in Changes of State

Changes of State (Phase Changes)

Thermochemistry.

Section 7.3—Changes in State

Thermochemical Calculations

How are they related? Chemistry and Energy.

Energy Transfer in the Hydrologic Cycle

Energy Transformations

Heat Exchange During Physical Changes

Heating and Cooling Curves

How are they related? Chemistry and Energy.

Chapter 10 “Thermochemistry”

Warm-up #2 Who do you agree with and why?

Chapter 11 Notes III Heat at State Changes.

Bellwork Wednesday Determine if the following are endothermic or exothermic. H = kJ/mol H = kJ/mol H = kJ/mol H = kJ/mol.

Thermochemistry Part 2.

Heating Curves Ice melts by absorbing heat, but without increasing temperature. 0oC solid  0oC liquid (avg KE stays same) HOW? …by changing phase.

Phase Changes, Heat of Fusion, and Heat of Vaporization

Jeopardy Freezing Melting Heat and Its Meas. Vapor Pressure

Bell Work: Exo or Endo? Absorbs heat. Releases heat.

Heats of Vaporization and Condensation

Heat in Changes of State

4/30 Opener Identify the following reactions as endo or exothermic:

A. Phase Changes Sublimation solid  gas

Chemistry 17.3.

Changes of State units: J/g Heat of Vaporization

Bellwork 3/6/18 What is energy? What units can energy be measured in?

Heating Curves and Phase Diagrams

Warm Up # 4 When the temperature for 45.0 grams of water decreases from 90.5oC to 7.0oC, how much energy is lost, in kilojoules? The specific heat of.

Thermochemistry.

2.3 Thermal Energy Transfer In The Hydrosphere.

Heat in Changes of State and Calculating Heat of Reaction

Heat of Reaction Heat of Solution Heats of Fusion and Vaporization

Warm Up #1 What is a catalyst?

Thermochemistry Chapter 17.

Introduction to Thermochemistry

States of Matter & Energy

Chapter 16: Energy and Chemical Change

Quick Review What is energy? How is it measured?

Introduction to Thermochemistry

Heating Curves and Enthalpy

Quick Review What is energy? How is it measured?

Presentation transcript:

Warm Up #2 In an endothermic reaction, if 350 J of heat is absorbed, how much heat is lost by the surroundings? How do you know? If the final temperature of 56.0 g of water was 95oC after 350 J of heat were added, find what the initial temperature of water is, given water’s specific heat of 4.18 J/(oC•g) Draw a diagram for an exothermic reaction. Show on this diagram how a catalyst would affect the reaction. Explain this in words. Is melting considered an endothermic or an exothermic process? What about condensation? How do you know?

Chapters 17.2-17.3 Measuring Heat

Review Heat (q) – TRANSFERRED from system to surroundings and vice versa (joules or calories) qsystem = -qsurroundings Endothermic vs. Exothermic Measuring Heat: q = m • c • ΔT C = specific heat – amt of energy it takes to raise 1 g of a substance up 1oC 1 kilojoule (kJ) = 1000 joules 1 kilocalorie = 1000 calories

ΔH and q ΔH = enthalpy – the heat content of a system at constant pressure ΔH = qsystem For endothermic reactions (melting): ΔH = positive For exothermic reactions (freezing) : ΔH = negative ΔH = kJ/mol

Measuring ΔH in Phase Changes Phase changes – going from one phase to another NO TEMP CHANGE, just heat added/taken away Liquid to solid = freezing (exo) Solid to liquid = melting (endo) Gas to liquid = condensation (exo) Liquid to gas = vaporization (endo)

Liquid Solid Phase Change ΔHfus = molar heat of fusion – amt of energy needed to melt 1 mol of solid substance (kJ/mol) For H2O: ΔHfus = 6.01 kJ/mol (endo) ΔHsolid = molar heat of solidification – opposite of fusion ΔHsolid for H2O = -6.01 kJ/mol (exo)

Liquid  Gas Phase Change ΔHvap = molar heat of vaporization – amt of energy needed to boil 1 mol of liquid substance (kJ/mol) For H2O: ΔHvap = 40.7 kJ/mol (endo) ΔHcond = molar heat of condensation– opposite of vaporization ΔHcond for H2O = -40.7 kJ/mol (exo)

Quick Quiz #2 Is vaporization an endothermic or an exothermic process? How do you know? How will that affect the energy in the system? How much energy is generated, in kilojoules, when you boil 78.0 grams of water? (ΔHvap = 40.7 kJ/mol ) If the molar heat of solidification of water is -6.01 KJ/mol, how much water, in grams, was frozen if 109 KJ of energy was released.