Video Tutorial on Energetics, Hess’s Law, Enthalpy of Formation and Combustion in Energetics. Prepared by Lawrence Kok http://lawrencekok.blogspot.com.

Slides:

Advertisements

Similar presentations

Chemistry Tutorial 5: Q4 Sit Han Yu 12S7F. Question Sulfur dioxide is a major pollutant from sulfuric acid plants. The SO 2 emitted into the atmosphere.

Advertisements

Thermochemistry Exothermic reactions release heat to the surroundings. Fe 2 O Al  2 Fe + Al 2 O kJ Potassium Permanganate Reaction Demo.

Topic c Bond energies and Enthalpies

Thermochemistry 2 Hess’s Law Heat of Formation Heat of Combustion Bond Enthalpy.

Enthalpy C 6 H 12 O 6 (s) + 6O 2 (g) --> 6CO 2 (g) + 6H 2 O(l) kJ 2C 57 H 110 O O 2 (g) --> 114 CO 2 (g) H 2 O(l) + 75,520 kJ The.

Chapter 11 (Practice Test)

Enthalpy EQ: How do you predict the sign of delta H?

Using Standard Molar Enthalpies of Formation SCH4U0.

Sections 5.4 – 5.6 Energy and Chemical Reactions.

Heat Transfer and Specific Heat Heat Transfer and Specific Heat Energy Changes in Chemical Reactions Energy Changes in Chemical Reactions Calculating ∆H.

Bomb Calorimetry constant volume often used for combustion reactions heat released by reaction is absorbed by calorimeter contents need heat capacity of.

Energetics IB Topics 5 & 15 PART 2: Calculating  H via Bond Enthalpies & Hess’s Law Above: thermit rxn.

Standard Enthalpy Changes =  H o P = 1 bar (0.997 atm) T = 298K, unless otherwise specified n = 1 mole for key compound.

Chapter 5- Part 2 Thermochemistry

It has been suggested that hydrogen gas obtained by the decomposition of water might be a substitute for natural gas (principally methane). To compare.

Enthalpy Change and Chemical Reactions

Chapter : Chemical Reactions That Involve Heat Suggested Reading: Pages

Bomb Calorimetry (Constant Volume Calorimetry)

Industrial Chemistry Hess’s law. Index Hess’s Law and its experimental verification Hess’s Law calculations, 4 examples. Hess’s Law.

Topic: Thermodynamics Do Now: packet p.1. Every physical or chemical change is accompanied by energy change  Energy released = _________________  Energy.

Chapter 5: Thermochemistry. Thermochemistry: – Energy Kinetic & Potential – First Law of Thermo internal energy, heat & work endothermic & exothermic.

THERMOCHEMISTRY Inneke Hantoro. INTRODUCTION Thermochemistry is the study of heat changes in chemical reactions. Almost all chemical reactions absorb.

Energetics HL and SL An exothermic reaction releases heat energy. An endothermic reaction takes in heat energy. During a chemical reaction bonds in the.

Thermochemistry 1 Hess’s Law Heat of Formation Heat of Combustion Bond Enthalpy.

Standard Enthalpies of Formation Learning Goal: You will be able to write formation equations, find the enthalpies of formation and use them & Hess’ Law.

Heat of reaction equations Using simultaneous equations.

ERT 108/3 PHYSICAL CHEMISTRY FIRST LAW OF THERMODYNAMICS Prepared by: Pn. Hairul Nazirah Abdul Halim.

UNIT 5 THERMOCHEMISTRY 1 A study of the energy produced by Chemical Reactions Chemical Reactions.

Topic 5: Energetics 5.1 Exothermic and endothermic reactions

Thermochemistry Chapter 12. Thermochemistry The study of the changes in the heat of chemical reactions. Heat – the energy that is transferred from one.

CHEMISTRY DEPARTMENT WAID ACADEMY ENTHALPY. The enthalpy of combustion of methanol, CH 3 OH, is -715 kJ mol -1. The mass of methanol which has to be burned.

Communicating Enthalpy Change. Method 1: Molar Enthalpies of Reaction, Δ r H m To communicate a molar enthalpy, both the substance and the reaction must.

Heat in Changes of State. What happens when you place an ice cube on a table in a warm room? Molar Heat of Fusion (ΔH fus ): heat absorbed by one mole.

Standard Enthalpy Changes of Reaction Section 15.1.

Hess’s Law: The algebraic addition of chemical equations yields a net equation whose enthalpy of reaction is the algebraic sum of the individual enthalpies.

It is impossible to measure enthalpy directly

The basis for calculating enthalpies of reaction is known as Hess’s law: the overall enthalpy change in a reaction is equal to the sum of enthalpy changes.

1. Definition Heat flow in a system SymbolH Like internal energy, the change in enthalpy is important State function – measure of its current conditions.

Energy: Standard Enthalpy of Formation and Reaction – Direct & Hess’s Law Enthalpy Enthalpy (H): heat flow for a chemical reaction. q constant P.

Enthalpies of Formation and Reaction Definitions: Standard state –A gas at 1 atm –An aqueous solution with a concentration of 1 M at a pressure of 1 atm.

Exothermic  When heat is released (given off) by the system into the surroundings, the process is exothermic  H = H final − H initial  H = H products.

Mass-Mass Stoichiometry If the mass of any reactant or product is known for a chemical reaction, it is possible to calculate the mass of the other reactants.

Exothermic and Endothermic Reactions. Chemical Reactions All chemical reactions involve bond breaking and bond forming. Energy is needed to break bonds.

Stoichiometry Chemistry 6.0. The Mathematics of Chemical Reactions: STOICHIOMETRY I. Balanced Chemical Equations A. Provide qualitative and quantitative.

Molar Enthalpy Recall that when we write a thermochemical equation the coefficients represent moles of particles Therefore, 1 H 2(g) + ½ O 2(g)  1 H 2.

Stoichiometry Notes (Chapter 12). Review of Molar Mass Recall that the molar mass of a compound is the mass, in grams, of one mole of that compound.

Ch 5: Thermochemistry. Nature of Energy (vocabulary) Thermodynamics: study of energy and its transformations Thermochemistry: study of relationships between.

3.1.4 Energetics review Calorimetry calculation

Standard Enthalpy Changes of Reaction – Define and apply the terms standard state, standard enthalpy change of formation (ΔH f ˚) and standard.

1.4 Energetics Practical 1.6 – Finding an enthalpy change that cannot be measured directly e. recall Hess’s Law and apply it to calculating enthalpy.

Section 4: Calculating Enthalpy Change

Industrial Chemistry Hess’s law.

Calculating various enthalpy changes

Hess’s Law and Standard Enthalpies of Formation

Enthalpy of Reactions -We can describe the energy absorbed as heat at constant pressure by the change in enthalpy (ΔH) -the enthalpy of a reaction is the.

List of enthalpies for several kinds of reactions.

Bell Ringer May 11th The law of conservation of energy: energy cannot be ________ or _______. It can only be ________ or __________.

Energy and Chemical Reactions

Hess’s Law and Standard Enthalpies of Formation Unit 10 Lesson 4

Enthalpy (∆H).

Hess’s Law and Standard Enthalpies of Formation Unit 10 Lesson 4

Thermodynamics Heat of Formation.

Energy and Chemical Reactions

1.2.5 Hess’s Law- the equation

Thermochemistry Lesson # 4: Hess’s Law.

Hess’s Law and Standard Enthalpies of Formation

How much heat energy is required (at constant pressure) to convert 50g of ice at 100K to liquid water at 315K given the following data: Cwater =

1.2.5 Hess’s Law- the equation

Presentation transcript:

Video Tutorial on Energetics, Hess’s Law, Enthalpy of Formation and Combustion in Energetics. Prepared by Lawrence Kok http://lawrencekok.blogspot.com

Video on Energetics and Enthalpy Calculation Enthalpy of reaction using combustion data Enthalpy of reaction using combustion data Enthalpy of reaction using formation data Enthalpy of reaction using formation data

Basic Rules for ΔH Enthalpy changes calculations 1 Total amt energy released/absorbed is α to number of moles of reactants 2 ΔH for reverse reaction is EQUAL in magnitude but opposite in sign to ΔH forward Standard condition for measuring STANDARD ENTHALPY CHANGE, ΔH 3 4 Unit for ΔH is KJ mol -1

Basic Rules for ΔH Enthalpy changes calculations Temp and Heat 5 Enthalpy change ΔH measured using a calorimeter 6 Specific heat capacity for a substance – water ( 4.18J g-1K-1) 7

Standard Enthalpy Change of Formation for a reaction, ΔHθ f

Standard Enthalpy Change of reaction, ΔHθ f ΔHθ f = Amt of energy absorbed or released when ONE mole of compound formed from Its standard state from its constituents in their standard states Ex : NaCI (s) + 1/2CI2 (g) → NaCI (s) Notes on ΔHθ f

Standard Enthalpy Change of reaction, ΔHθ f ΔHθ f = Amt of energy absorbed or released when ONE mole of compound formed from Its standard state from its constituents in their standard states Ex : NaCI (s) + 1/2CI2 (g) → NaCI (s)

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 1 Calculate the ΔHθ ,enthalpy change for the reaction below 4 CH3NHNH2 + 5 N2O4 → 4CO2 + 12 H2O + 9N2 Steps 1

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 1 Calculate the ΔHθ ,enthalpy change for the reaction below 4 CH3NHNH2 + 5 N2O4 → 4CO2 + 12 H2O + 9N2 Steps 1 2 Formation of reactants data Formation of products data

Ans Calculate the ΔHθ ,enthalpy change for the reaction below 4 CH3NHNH2 + 5 N2O4 → 4CO2 + 12 H2O + 9N2

Calculate the ΔHθ ,enthalpy change for the reaction below Ans Calculate the ΔHθ ,enthalpy change for the reaction below 4 CH3NHNH2 + 5 N2O4 → 4CO2 + 12 H2O + 9N2 Ans Formation data

Ex 2 Calculate the ΔHθ ,enthalpy change for the reaction below NH4NO3 → N2O + 2 H2O using energy cycle diagram

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 2 Calculate the ΔHθ ,enthalpy change for the reaction below NH4NO3 → N2O + 2 H2O using energy cycle diagram Ans Formation data

Ex 2 Calculate the ΔHθ ,enthalpy change for the reaction below NH4NO3 → N2O + 2 H2O using energy level diagram

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 2 Calculate the ΔHθ ,enthalpy change for the reaction below NH4NO3 → N2O + 2 H2O using energy level diagram Ans Formation data

Ex 3 Calculate the ΔHθ ,enthalpy change for the reaction below C2H6 + 7/2O2 → 2CO2 + 3 H2O using energy cycle diagram

Ex 3 Calculate the ΔHθ ,enthalpy change for the reaction below C2H6 + 7/2O2 → 2CO2 + 3 H2O using energy cycle diagram Ans

Ex 3 Calculate the ΔHθ ,enthalpy change for the reaction below C2H6 + 7/2O2 → 2CO2 + 3 H2O using energy level diagram

Ex 3 Calculate the ΔHθ ,enthalpy change for the reaction below C2H6 + 7/2O2 → 2CO2 + 3 H2O using energy level diagram Ans

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 4 Calculate the ΔHθ ,enthalpy change for the reaction below C2H4 + H2 → C2H6

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 4 Calculate the ΔHθ ,enthalpy change for the reaction below C2H4 + H2 → C2H6 Energy Cycle diagram Ans

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 4 Calculate the ΔHθ ,enthalpy change for the reaction below C2H4 + H2 → C2H6 Energy Cycle diagram or Energy Level Diagram Ans Answer the same = -137kJmol-1

Ex 5 Write balanced equation and calculate the ΔHθ for the following reactions Zinc + Chlorine forming zinc chloride b) Hydrogen sulfide + sulfur dioxide forming sulfur and water c) Lead (II) nitrate decomposing to lead (II) oxide, nitrogen dioxide and oxygen

Ex 4 Write balanced equation and calculate the ΔHθ for the following reactions Zinc + Chlorine forming zinc chloride b) Hydrogen sulfide + sulfur dioxide forming sulfur and water c) Lead (II) nitrate decomposing to lead (II) oxide, nitrogen dioxide and oxygen

Standard Enthalpy Change of combustion, ΔHθ c

Standard Enthalpy Change of combustion, ΔHθ c ΔHθ c = Amt of energy released when ONE mole of substance completely burnt in OXYGEN under standard conditions Notes on combustion

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 1 Calculate the ΔHθ ,enthalpy change for the reaction below 2 C + 3H2 → C2H6 Using Energy Cycle Diagram

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 1 Calculate the ΔHθ ,enthalpy change for the reaction below 2 C + 3H2 → C2H6 Using Energy Cycle Diagram Ans

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 2 Calculate the ΔHθ ,enthalpy change for the reaction below 1st method Using Energy Cycle Diagram 2 C + 2H2 → C2H4

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 2 Calculate the ΔHθ ,enthalpy change for the reaction below 1st method Using Energy Cycle Diagram 2 C + 2H2 → C2H4 Ans

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 2 Calculate the ΔHθ ,enthalpy change for the reaction below 2nd method Using Energy Level Diagram 2 C + 2H2 → C2H4

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 2 Calculate the ΔHθ ,enthalpy change for the reaction below 2nd method Using Energy Level Diagram 2 C + 2H2 → C2H4 Ans

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 3 Calculate the ΔHθ ,enthalpy change for the reaction below 1st method Using Energy Cycle Diagram 2 C + 3H2 + 1/2O2 → C2H5OH

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 3 Calculate the ΔHθ ,enthalpy change for the reaction below 1st method Using Energy Cycle Diagram 2 C + 3H2 + 1/2O2 → C2H5OH Ans

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 3 Calculate the ΔHθ ,enthalpy change for the reaction below 2nd method Using Energy Level Diagram 2 C + 3H2 + 1/2O2 → C2H5OH

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 3 Calculate the ΔHθ ,enthalpy change for the reaction below 2nd method Using Energy Level Diagram 2 C + 3H2 + 1/2O2 → C2H5OH Ans

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 4 Calculate the ΔHθ ,enthalpy change for the reaction below TWO methods 1st method, using combustion data 2 C + 3H2 + 1/2O2→ C2H5OH Combustion data

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 4 Calculate the ΔHθ ,enthalpy change for the reaction below TWO methods 1st method, using combustion data 2 C + 3H2 + 1/2O2→ C2H5OH Ans Combustion data

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 4 Calculate the ΔHθ ,enthalpy change for the reaction below 2nd method, using formation data 2 C + 3H2 + 1/2O2→ C2H5OH Formation data

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 4 Calculate the ΔHθ ,enthalpy change for the reaction below 2nd method, using formation data 2 C + 3H2 + 1/2O2→ C2H5OH Formation data Ans

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 5 Calculate the ΔHθ ,enthalpy change for the reaction below Using combustion data 3C2H2 → C6H6 Combustion data

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 5 Calculate the ΔHθ ,enthalpy change for the reaction below Using combustion data 3C2H2 → C6H6 Ans Combustion data

Calculate ΔHθ c ,enthalpy change for combustion of propene shown below Ex 6 Calculate ΔHθ c ,enthalpy change for combustion of propene shown below Using combustion /formation data 3CH2 =CHCH3 + 9/2O2 → 3CO2 + 3H2O6

Calculate ΔHθ c ,enthalpy change for combustion of propene shown below Ex 6 Calculate ΔHθ c ,enthalpy change for combustion of propene shown below Using combustion /formation data 3CH2 =CHCH3 + 9/2O2 → 3CO2 + 3H2O6 Ans

Calculate the ΔHθ ,enthalpy change for the reaction below Ex 7 Calculate the ΔHθ ,enthalpy change for the reaction below C2H4 + H2 → C2H6 Using Energy Cycle Diagram Using Energy Level Diagram Answer the same = -137kJmol-1

Video on Energetics and Enthalpy Calculation Using equation method to solve ΔH Using equation method to solve ΔH Using formation enthalpy to solve ΔH (Khan Academy) Concept on enthalpy, ΔH (Khan Academy)

Acknowledgements Thanks to source of pictures and video used in this presentation Thanks to Creative Commons for excellent contribution on licenses http://creativecommons.org/licenses/ Prepared by Lawrence Kok Check out more video tutorials from my site and hope you enjoy this tutorial http://lawrencekok.blogspot.com