Thermochemistry. Energy. Heat. Energy is the capacity to do work. Forms of energy: The SI unit for energy is J (joule).

Size: px
Start display at page:

Download "Thermochemistry. Energy. Heat. Energy is the capacity to do work. Forms of energy: The SI unit for energy is J (joule)."

Transcription

1 Thermochemistry Study of heat change in chemical reactions Chapter 6 Energy Energy is the capacity to do work. Forms of energy: kinetic energy (energy of motion) potential energy (stored energy energy of an object due to its position, condition, or composition). The SI unit for energy is J (joule). Heat Heat is a form of energy associated with the motion of atoms or molecules. Heat is capable of being transmitted through solid & fluid media by conduction through fluid media by convection through empty space by radiation. 1

2 Thermodynamic Concepts System Substances involved in the chemical & physical changes that we are studying Surroundings Everything in the system s environment Universe System plus its surroundings Exothermic/Endothermic Exothermic processes give off heat burning of natural gas Endothermic processes absorb heat melting of ice Thermodynamic State of the System Set of conditions that completely describe the properties of the system Temperature Pressure Composition (what and how many moles) Physical state 2

3 State Properties Properties of the system such as P, V, T are called State Functions The value of the state function depends only on the state of the system and not the way in which the system came to be in that state A change in a state function describes the difference between the 2 states Independent of the pathway of the change First Law of Thermodynamics The total amount of energy in the universe is constant Energy can be converted to one form or another, but can not be created or destroyed d Energy is neither created or destroyed in ordinary chemical reactions and physical changes Changes in Internal Energy of a System From a Chemical Reaction ΔE = heat + work = q + w = heat absorbed by the system + work done on the system The first law of thermodynamics says that energy can not be created or destroyed, so it has to go somewhere either heat or work 3

4 Sign Convention q is positive Heat is absorbed by the system from its surroundings (endothermic) q is negative Heat is released by the system to the surrounding (exothermic) w is positive Work is done on the system by the surroundings w is negative Work is done by the system on the surroundings 1 st Law of Thermodynamics Whenever energy is added or removed from a system either as heat or work the energy of the surroundings changes by that same amount Another way of expressing the 1 st Law of Thermodynamics The total amount of energy in the universe is constant Pressure-Volume Work The most common type of work involved in chemical reactions and physical changes is pressure-volume work Pressure is Force/unit area ( distance squared) - d 2 Volume is distance cubed d 3 WorFd3kw Fd= = d2= 4

5 Pressure-Volume Work In a chemical reaction, when a gas is produced at constant pressure The gas does work as it expands against the pressure In a chemical reaction, when a gas is consumed the atmosphere (pressure) does work on the reacting system Pressure-Volume Work Work done on or by the system depends upon the external pressure and the volume Work done by the system therefore e e negative At constant pressure (such as atmospheric pressure) Work = - P ΔV = - P (V Prods V Rxts ) Units for PV work would be L-atm 1L-atm = J Pressure-Volume Work Calculate the amount of work done if a gas expands from 1.0 L to 10.0 L, when external pressure is 1.0 atm (at constant temperature). W = - P V = - P (V final V initial ) 1 L-atm = J -912 J 5

6 Pressure-Volume Work ΔE = q + w ΔE = q - PΔV (at constant pressure) When the change in volume is zero (equal number of moles of gases are produced and consumed) ΔE = q The amount of heat absorbed or released by the system Pressure Volume Work ΔE = q - PΔV (at constant pressure) Ideal gas Law says PΔV = ΔnRT R = J/K-mol T = K ΔE = q - ΔnRT (at constant pressure) Δn = no. of moles of gaseous products - no. of moles of gaseous reactants Pressure Volume Work (PΔV) When the number of moles of gaseous products is greater than the number of moles of gaseous reactants (Δn is positive), w is negative and work is done by the system on the surroundings When the number of moles of gaseous products is less than the number of moles of gaseous reactants (Δn is negative), w is positive and work is done on the system by the surroundings 6

7 Enthalpy H Enthalpy (H) of a system is defined as: H = E + PV Where E is the internal energy of the system and PV is Pressure-Volume System t Heat Enthalpy has energy units J We can t measure the absolute value of H directly, but we can measure a change in enthalpy (ΔH) ΔH = ΔE + P Δ V (at constant T,P) Change in Enthalpy ΔH Enthalpy change ΔH The amount of heat transferred into or out of a system as it undergoes a chemical or physical change at constant pressure ΔH = H final - H initial ΔH = H products - H reactants Because ΔH is only dependent upon the initial and final state of the system, it is state function ΔH By Convention Endothermic processes have a positive ΔH (ΔH > 0) - they absorb b heat Exothermic processes have a negative ΔH (ΔH < 0) - they release heat 7

8 Thermochemical Equations C 2 H 5 OH (l) + 3O 2(g) 2CO 2(g) + 3H 2 O (l) kj 1367 kj per mole of reaction 1367 kj per mole of C 2 H 5 OH 1367 kj per 3 mole of O 2 C 2 H 5 OH (l) + 3O 2(g) 2CO 2(g) + 3H 2 O (l) ΔH = kj Thermochemical Equations CH 3 OCH 3(l) + 3 O 2(g) 2 CO 2(g) + 3 H 2 O (l) When 2.61 g of CH 3 OCH 3 is burned at constant pressure, 82.5 kj of heat is evolved. Calculate the ΔH for the reaction. Find out how much heat for one mole of CH 3 OCH 3. FW = 46.0 g/mole Add the negative sign, since it is exothermic Thermochemical Equations 4 Al (s) + 3 O 2(g) 2 Al 2 O 3(s) ΔH = kj/rxn mol How much heat is evolved if 24.2 g of Al is used? 8

9 Thermochemical Equations 4 Al (s) + 3 O 2(g) 2 Al 2 O 3(s) ΔH = kj/rxn mol How much heat is evolved if 24.2 g of Al is used? 24.2 g Al 1 mol Al 1 rxn mol kj g Al 4 mol Al 1 rxn mol = 752 kj Standard States Thermodynamic Standard State The most stable, pure form under standard pressure (1 atm) and at some specified temperature (25 C unless otherwise stated) O 2 (g) gaseous diatomic oxygen Na (s) solid sodium metal C (s) graphite solid H 2 O (l) liquid water Standard State Conventions 1. For a pure substance in the liquid or solid phase, the standard state is the pure liquid or solid 2. For a gas, the standard state is the gas at a pressure of one atmosphere; In a mixture the partial pressure must be 1 atmosphere 3. For a substance in solution, the standard state refers to 1 M concentration 9

10 Standard Enthalpy Change ΔH rxn Change in enthalpy (ΔH) when a specified number of moles of reactants, t all at standard d states, t are converted completely to the specified number of moles of products, all at standard states ΔH f Standard molar enthalpy of formation ΔH for the reaction in which one mole substance in a specified state is formed from its elements in their standard states By convention, ΔH f value of any element in its standard state is zero Thermodynamic Formation Reactions H 2(g) + ½ O 2(g) H 2 O (l) ΔH o f = KJ/mol Cu (s) + ½ O 2(g) CuO (s) ΔH o f = -157 KJ/mol 3C (graphite) + 4H 2(g) C 3 H 8(g) ΔH o f = KJ/mol Hg (l) + Cl 2(g) HgCl 2(s) ΔH o f = -224 KJ/mol See Table 6-4 of Text to obtain ΔH o f values 10

11 Standard Molar Enthalpies at 298 K Substance ΔH f (kj/mole) Br 2 (l) 0 Br 2 (g) C (diamond) C (graphite) 0 CH 4 (g) C 2 H 4 (g) CaCO 3 (s) C 2 H 5 OH(l) Hess Law The change of enthalpy for a chemical reaction is the same whether it occurs by one step or by any series of steps Enthalpy is State Function Independent of pathway ΔH o rxn = ΔH o a + ΔH o b + ΔH o c +. Hess s Law C (graphite) + 1/2 O 2(g) CO (g) ΔH o rxn =? C + o (graphite) O 2(g) CO 2(g) H rxn = kj/mol CO 2(g) CO (g) + 1/2 O 2(g) H o rxn = kj/mol C (graphite) + 1/2 O 2(g) CO (g) H o rxn = kj/mol Heats of reactions experimentally determined in the lab 11

12 Hess s Law Elements ΔH o rxn = Σ n ΔH o f products Σn ΔH o f products Σn ΔH o f reactants - Σ n ΔH o f reactants Energy Reactants ΔH o f rxn Products Hess s Law Application NH 4 NO 3(s) N 2 O (g) + 2H 2 O (g) ΔH o rxn =? NH 4 NO 3(s) ΔH o f = kj/mol N 2 O (g) ΔH o f = 82.0 kj/mol H 2 O (g) ΔH o f = kj/mol ΔH o rxn = kj/mol ΔH f o Hess s Law: ΔH rxn =? SiH 4(g) + 2 O 2(g) SiO 2(s) + 2H 2 O ( l ) kj/mol Use ΔH fo and Hess s law to calculate the heat of reaction. 12

13 C 2 H 4(g) + H 2 O (l) C 2 H 5 OH (l) ΔH rxn =? Known Equations: C 2 H 5 OH (l) + 3 O 2(g) 2 CO 2(g) + 3 H 2 O (l) C 2 H 4(g) + 3 O 2(g) 2 CO 2(g) + 2 H 2 O (l) ΔH = kj ΔH = kj ΔH = -44 kj Specific Heat (s) The amount of heat required to raise the temperature 1 g of a substance 1 C. The units of specific heat are J/g- C. This is an intrinsic property of a pure material. Specific Heat How much heat is required to raise liquid 10.0 g of water 10.0 C. The specific heat of liquid water is J/g- C. q= m s ΔT 418 J 13

14 Heat Capacity Heat Capacity (C) is the amount of heat required to raise the temperature of a given quantity of substance one degree Celsius C = m s m = mass s = specific heat q= C ΔT Calorimetry A calorimeter is an instrument used to measure the energy change associated with a physical or chemical change Based on observing the temperature change when a system absorbs or releases energy in the form of heat The temperature change of a known substance (usually water) of known specific heat (J/g- o C) is measured The volume of the calorimeter is constant (ΔE = q) Picture by Dr. Gary Bertrand - Calorimetry Amount of Heat released/absorbed by the reaction = Amount of heat gained/lost by the calorimeter ( constant ) plus (+) Amount of heat gained/lost by the solution This is just the first law of thermodynamics. 14

15 Calorimetry C 2 H 5 OH (l) + 2O 2(g) 2CO 2(g) + 3H 2 O (l) g of C 2 H 5 OH (MW =46.07 g/mol) Specific heat of Calorimeter (calorimeter constant) = 2.71 kj/ o C The calorimeter contains 3000 g of H 2 0. The specific heat of water is J/g- o C Starting Temperature = o C Final Temperature = o C What is H (kj/mol) for this reaction? Calorimeter Constant We add kj of heat to a calorimeter that contains g of water. The temperature of the water and the calorimeter, originally at C, increases to C. Calculate the heat capacity of the calorimeter in J/ C. The specific heat of water is J/g C. Calorimetry 50.0 ml of H 2 O at 53.0 C is add to 50.0 ml of H 2 O at 22.0 C in a coffee cup calorimeter. The final temperature of the mixture was 37.0 C. Specific Heat of water = J/g- C. How much heat is lost by hot water (J)? How much heat is gained by room temperature water (J)? What is the calorimeter constant (heat capacity of the calorimeter), J/ C? 13.9 J/ C 15

16 Calorimetry ml of 1.00 M HCl and ml of 1.05 M NaOH both at C are mixed in the coffee cup calorimeter The final temperature of the resulting mixture is C The density of resulting NaCl solution is 1.04 g/ml The specific heat of the NaCl solution is 3.89 J/g C The calorimeter heat capacity is 13.9 J/ C Calculate the molar heat of reaction ΔH = KJ/mol H H of Physical Processes Change in enthalpy ( H) can be measured for physical processes, not just chemical reactions Phase Changes Evaporation absorbs heat ( H positive) Condensation releases heat ( H negative) Melting? Freezing? Heat of Solution Dissolution of ionic solids into solutions results in heat absorption or heat release Energy must be input to overcome the lattice energy which holds the solid together Energy is released upon dissolution of ions The energy balance determines whether the overall process is endothermic or exothermic 16

17 Heat of Dilution Dilution of solutions into solutions results in heat absorption or heat release If the dissolution process is endothermic, then the dilution process will absorb more heat (get cooler) If the dissolution process is exothermic, then the dilution process will release more heat (get hotter) Heat of Dilution The dilution process for sulfuric acid (H 2 SO 4 ) is extremely exothermic Because of this, you should never add water to sulfuric acid to dilute it To dilute, always add sulfuric acid to water 17

ENERGY. Thermochemistry. Heat. Temperature & Heat. Thermometers & Temperature. Temperature & Heat. Energy is the capacity to do work.

ENERGY. Thermochemistry. Heat. Temperature & Heat. Thermometers & Temperature. Temperature & Heat. Energy is the capacity to do work. ENERGY Thermochemistry Energy is the capacity to do work. Chapter 6 Kinetic Energy thermal, mechanical, electrical, sound Potential Energy chemical, gravitational, electrostatic Heat Heat, or thermal energy,

More information

Chapter 5 Thermochemistry

Chapter 5 Thermochemistry Chapter 5 Thermochemistry I. Nature of Energy Energy units SI unit is joule, J From E = 1/2 mv 2, 1J = 1kg. m 2 /s 2 Traditionally, we use the calorie as a unit of energy. 1 cal = 4.184J (exactly) The

More information

Thermochemistry. Thermochemistry 1/25/2010. Reading: Chapter 5 (omit 5.8) As you read ask yourself

Thermochemistry. Thermochemistry 1/25/2010. Reading: Chapter 5 (omit 5.8) As you read ask yourself Thermochemistry Reading: Chapter 5 (omit 5.8) As you read ask yourself What is meant by the terms system and surroundings? How are they related to each other? How does energy get transferred between them?

More information

THERMOCHEMISTRY & DEFINITIONS

THERMOCHEMISTRY & DEFINITIONS THERMOCHEMISTRY & DEFINITIONS Thermochemistry is the study of the study of relationships between chemistry and energy. All chemical changes and many physical changes involve exchange of energy with the

More information

Name Date Class THERMOCHEMISTRY. SECTION 17.1 THE FLOW OF ENERGY HEAT AND WORK (pages 505 510)

Name Date Class THERMOCHEMISTRY. SECTION 17.1 THE FLOW OF ENERGY HEAT AND WORK (pages 505 510) 17 THERMOCHEMISTRY SECTION 17.1 THE FLOW OF ENERGY HEAT AND WORK (pages 505 510) This section explains the relationship between energy and heat, and distinguishes between heat capacity and specific heat.

More information

Chapter 5. Thermochemistry

Chapter 5. Thermochemistry Chapter 5. Thermochemistry THERMODYNAMICS - study of energy and its transformations Thermochemistry - study of energy changes associated with chemical reactions Energy - capacity to do work or to transfer

More information

Chapter 5 Energy Relationships in Chemistry: Thermochemistry

Chapter 5 Energy Relationships in Chemistry: Thermochemistry Chapter 5 Energy Relationships in Chemistry: Thermochemistry In order to study thermochemical changes, we first have to define (a) system that specify part of the universe of interest to us. (b) surrounding

More information

CHM111 Lab Enthalpy of Hydration of Sodium Acetate Grading Rubric

CHM111 Lab Enthalpy of Hydration of Sodium Acetate Grading Rubric Name Team Name CHM111 Lab Enthalpy of Hydration of Sodium Acetate Grading Rubric Criteria Points possible Points earned Lab Performance Printed lab handout and rubric was brought to lab 3 Safety and proper

More information

3. Of energy, work, enthalpy, and heat, how many are state functions? a) 0 b) 1 c) 2 d) 3 e) 4 ANS: c) 2 PAGE: 6.1, 6.2

3. Of energy, work, enthalpy, and heat, how many are state functions? a) 0 b) 1 c) 2 d) 3 e) 4 ANS: c) 2 PAGE: 6.1, 6.2 1. A gas absorbs 0.0 J of heat and then performs 15.2 J of work. The change in internal energy of the gas is a) 24.8 J b) 14.8 J c) 55.2 J d) 15.2 J ANS: d) 15.2 J PAGE: 6.1 2. Calculate the work for the

More information

DETERMINING THE ENTHALPY OF FORMATION OF CaCO 3

DETERMINING THE ENTHALPY OF FORMATION OF CaCO 3 DETERMINING THE ENTHALPY OF FORMATION OF CaCO 3 Standard Enthalpy Change Standard Enthalpy Change for a reaction, symbolized as H 0 298, is defined as The enthalpy change when the molar quantities of reactants

More information

Absorption of Heat. Internal energy is the appropriate energy variable to use at constant volume

Absorption of Heat. Internal energy is the appropriate energy variable to use at constant volume 6 Absorption of Heat According to the First Law, E = q + w = q - P V, assuming P-V work is the only kind that can occur. Therefore, E = q V. The subscript means that the process occurs at constant volume.

More information

Enthalpy changes and calorimetry. Enthalpy changes in reactions Calorimetry and heat measurement Hess s Law Heats of formation

Enthalpy changes and calorimetry. Enthalpy changes in reactions Calorimetry and heat measurement Hess s Law Heats of formation Enthalpy changes and calorimetry Enthalpy changes in reactions Calorimetry and heat measurement Hess s Law Heats of formation Learning objectives Describe the standard state for thermodynamic functions

More information

Calorimetry and Enthalpy. Chapter 5.2

Calorimetry and Enthalpy. Chapter 5.2 Calorimetry and Enthalpy Chapter 5.2 Heat Capacity Specific heat capacity (c) is the quantity of thermal energy required to raise the temperature of 1g of a substance by 1⁰C The units for specific heat

More information

Bomb Calorimetry. Example 4. Energy and Enthalpy

Bomb Calorimetry. Example 4. Energy and Enthalpy Bomb Calorimetry constant volume often used for combustion reactions heat released by reaction is absorbed by calorimeter contents need heat capacity of calorimeter q cal = q rxn = q bomb + q water Example

More information

Thermochemical equations allow stoichiometric calculations.

Thermochemical equations allow stoichiometric calculations. CHEM 1105 THERMOCHEMISTRY 1. Change in Enthalpy ( H) Heat is evolved or absorbed in all chemical reactions. Exothermic reaction: heat evolved - heat flows from reaction mixture to surroundings; products

More information

Thermochemistry is study of changes in energy (heat) associated with physical or chemical changes.

Thermochemistry is study of changes in energy (heat) associated with physical or chemical changes. Thermochem 1 Thermochemistry Thermochemistry and Energy and Temperature Thermochemistry is study of changes in energy (heat) associated with physical or chemical changes. Force = push F= m a (mass x acceleration)

More information

L q + w. CHM 1041 Thermochemistry Heats of Solution (Reaction) J. Bieber. Section: Date:

L q + w. CHM 1041 Thermochemistry Heats of Solution (Reaction) J. Bieber. Section: Date: CHM 1041 Thermochemistry Heats of Solution (Reaction) J. Bieber Name: Partner: Section: Date: To study quantitatively the heat of solution when (1) a salt dissolves in water and (2) to study the heats

More information

Unit 5 Practice Test. Name: Class: Date: Multiple Choice Identify the choice that best completes the statement or answers the question.

Unit 5 Practice Test. Name: Class: Date: Multiple Choice Identify the choice that best completes the statement or answers the question. Name: Class: Date: Unit 5 Practice Test Multiple Choice Identify the choice that best completes the statement or answers the question. 1) The internal energy of a system is always increased by. A) adding

More information

Calorimeter: A device in which the heat associated with a specific process is measured.

Calorimeter: A device in which the heat associated with a specific process is measured. 1 CALORIMETRY p. 661-667 (simple), 673-675 (bomb) Calorimeter: A device in which the heat associated with a specific process is measured. There are two basic types of calorimeters: 1. Constant-pressure

More information

Chapter 20. Thermodynamics p. 811 842. Spontaneity. What have we learned about spontaneity during this course?

Chapter 20. Thermodynamics p. 811 842. Spontaneity. What have we learned about spontaneity during this course? Chapter 20 p. 811 842 Spontaneous process: Ex. Nonspontaneous process: Ex. Spontaneity What have we learned about spontaneity during this course? 1) Q vs. K? 2) So.. Spontaneous process occurs when a system

More information

Thermodynamics- Chapter 19 Schedule and Notes

Thermodynamics- Chapter 19 Schedule and Notes Thermodynamics- Chapter 19 Schedule and Notes Date Topics Video cast DUE Assignment during class time One Review of thermodynamics 1_thermo_review AND Review of thermo Wksheet 2.1ch19_intro Optional: 1sc_thermo

More information

Thermodynamics: First Law, Calorimetry, Enthalpy. Calorimetry. Calorimetry: constant volume. Monday, January 23 CHEM 102H T.

Thermodynamics: First Law, Calorimetry, Enthalpy. Calorimetry. Calorimetry: constant volume. Monday, January 23 CHEM 102H T. Thermodynamics: First Law, Calorimetry, Enthalpy Monday, January 23 CHEM 102H T. Hughbanks Calorimetry Reactions are usually done at either constant V (in a closed container) or constant P (open to the

More information

AP* Chemistry THERMOCHEMISTRY

AP* Chemistry THERMOCHEMISTRY AP* Chemistry THERMOCHEMISTRY Terms for you to learn that will make this unit understandable: Energy (E) the ability to do work or produce heat ; the sum of all potential and kinetic energy in a system

More information

Chapter 5: thermochemstry. Internal Energy: E

Chapter 5: thermochemstry. Internal Energy: E Chapter 5: thermochemstry tonight s goals Energy and Enthalpy Review Enthalpies of Reaction Calorimetry Hess Law Enthalpies of Formation Internal Energy: E E = The sum of all kinetic and potential energies

More information

Enthalpy of Neutralization. Introduction

Enthalpy of Neutralization. Introduction Enthalpy of Neutralization Introduction Energy changes always accompany chemical reactions. If energy, in the form of heat, is liberated the reaction is exothermic and if energy is absorbed the reaction

More information

Procedure. Day 1 - Calibration of the Calorimeter. (Part I) The Heat Capacity of the Calorimeter.

Procedure. Day 1 - Calibration of the Calorimeter. (Part I) The Heat Capacity of the Calorimeter. Thermochemistry Experiment 10 Thermochemistry is the study of the heat energy involved in chemical reactions and changes of physical state. Heat energy is always spontaneously transferred from hotter to

More information

UNIT 1 THERMOCHEMISTRY

UNIT 1 THERMOCHEMISTRY UNIT 1 THERMOCHEMISTRY THERMOCHEMISTRY LEARNING OUTCOMES Students will be expected to: THERMOCHEMISTRY STSE analyse why scientific and technological activities take place in a variety individual and group

More information

Thermodynamics. Thermodynamics 1

Thermodynamics. Thermodynamics 1 Thermodynamics 1 Thermodynamics Some Important Topics First Law of Thermodynamics Internal Energy U ( or E) Enthalpy H Second Law of Thermodynamics Entropy S Third law of Thermodynamics Absolute Entropy

More information

Chem 1A Exam 2 Review Problems

Chem 1A Exam 2 Review Problems Chem 1A Exam 2 Review Problems 1. At 0.967 atm, the height of mercury in a barometer is 0.735 m. If the mercury were replaced with water, what height of water (in meters) would be supported at this pressure?

More information

Heats of Transition, Heats of Reaction, Specific Heats, and Hess s Law

Heats of Transition, Heats of Reaction, Specific Heats, and Hess s Law Heats of Transition, Heats of Reaction, Specific Heats, and Hess s Law GOAL AND OVERVIEW A simple calorimeter will be made and calibrated. It will be used to determine the heat of fusion of ice, the specific

More information

Sample Exercise 15.1 Writing Equilibrium-Constant Expressions

Sample Exercise 15.1 Writing Equilibrium-Constant Expressions Sample Exercise 15.1 Writing Equilibrium-Constant Expressions Write the equilibrium expression for K c for the following reactions: Solution Analyze: We are given three equations and are asked to write

More information

SUGGESTION ANSWER SCHEME CHAPTER 8: THERMOCHEMISTRY. 1 (a) Use the data in the table below to answer the following questions:

SUGGESTION ANSWER SCHEME CHAPTER 8: THERMOCHEMISTRY. 1 (a) Use the data in the table below to answer the following questions: SUGGESTION ANSWER SCHEME CHAPTER 8: THERMOCHEMISTRY ANSWER SCHEME UPS 2004/2005 SK027 1 (a) Use the data in the table below to answer the following questions: Enthalpy change ΔH (kj/mol) Atomization energy

More information

1. Thermite reaction 2. Enthalpy of reaction, H 3. Heating/cooling curves and changes in state 4. More thermite thermodynamics

1. Thermite reaction 2. Enthalpy of reaction, H 3. Heating/cooling curves and changes in state 4. More thermite thermodynamics Chem 105 Fri 10-23-09 1. Thermite reaction 2. Enthalpy of reaction, H 3. Heating/cooling curves and changes in state 4. More thermite thermodynamics 10/23/2009 1 Please PICK UP your graded EXAM in front.

More information

1/7/2013. Chapter 10. Energy Changes in Chemical Reactions. Chemistry: Atoms First Julia Burdge & Jason Overby. Thermochemistry

1/7/2013. Chapter 10. Energy Changes in Chemical Reactions. Chemistry: Atoms First Julia Burdge & Jason Overby. Thermochemistry /7/03 Chemistry: Atoms First Julia Burdge & Jason Overby 0 Thermochemistry Chapter 0 Energy Changes in Chemical Reactions Kent L. McCorkle Cosumnes River College Sacramento, CA Copyright (c) The McGraw-Hill

More information

Chemistry 13: States of Matter

Chemistry 13: States of Matter Chemistry 13: States of Matter Name: Period: Date: Chemistry Content Standard: Gases and Their Properties The kinetic molecular theory describes the motion of atoms and molecules and explains the properties

More information

I. CALORIMETRY CALORIMETRY

I. CALORIMETRY CALORIMETRY CALORIMETRY I. CALORIMETRY If the process (e.g. chemical reaction, phase conversion) requires heat to proceed, it is said to be endothermic. For endothermic process, q > 0. If the process (e.g. chemical

More information

Example. c. Calculate the amount of heat (in kj) required to heat 1.00 kg (~1 L) of water at 25 C to its boiling point.

Example. c. Calculate the amount of heat (in kj) required to heat 1.00 kg (~1 L) of water at 25 C to its boiling point. Example When consuming an ice-cold drink, one must raise the temperature of the beverage to 37.0 C (normal body temperature). Can one lose weight by drinking ice-cold beverages if the body uses up about

More information

Energy Flow in Marine Ecosystem

Energy Flow in Marine Ecosystem Energy Flow in Marine Ecosystem Introduction Marin ecosystem is a functional system and consists of living groups and the surrounding environment It is composed of some groups and subgroups 1. The physical

More information

ENTHALPY CHANGES FOR A CHEMICAL REACTION scaling a rxn up or down (proportionality) quantity 1 from rxn heat 1 from Δ r H. = 32.

ENTHALPY CHANGES FOR A CHEMICAL REACTION scaling a rxn up or down (proportionality) quantity 1 from rxn heat 1 from Δ r H. = 32. CHEMISTRY 103 Help Sheet #10 Chapter 4 (Part II); Sections 4.6-4.10 Do the topics appropriate for your lecture Prepared by Dr. Tony Jacob http://www.chem.wisc.edu/areas/clc (Resource page) Nuggets: Enthalpy

More information

Name Class Date. In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question.

Name Class Date. In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. Assessment Chapter Test A Chapter: States of Matter In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. 1. The kinetic-molecular

More information

Standard Free Energies of Formation at 298 K. Average Bond Dissociation Energies at 298 K

Standard Free Energies of Formation at 298 K. Average Bond Dissociation Energies at 298 K 1 Thermodynamics There always seems to be at least one free response question that involves thermodynamics. These types of question also show up in the multiple choice questions. G, S, and H. Know what

More information

Energy and Chemical Reactions. Characterizing Energy:

Energy and Chemical Reactions. Characterizing Energy: Energy and Chemical Reactions Energy: Critical for virtually all aspects of chemistry Defined as: We focus on energy transfer. We observe energy changes in: Heat Transfer: How much energy can a material

More information

Transfer of heat energy often occurs during chemical reactions. A reaction

Transfer of heat energy often occurs during chemical reactions. A reaction Chemistry 111 Lab: Thermochemistry Page I-3 THERMOCHEMISTRY Heats of Reaction The Enthalpy of Formation of Magnesium Oxide Transfer of heat energy often occurs during chemical reactions. A reaction may

More information

Chemistry 1215 Make up Lab Enthalpy of Neutralization

Chemistry 1215 Make up Lab Enthalpy of Neutralization hemistry 1215 Make up Lab Enthalpy of Neutralization Objective In this experiment you will determine the molar enthalpy of neutralization of an acid. Introduction The study of energy and its transformations

More information

Thermodynamics. S (reactants) S S (products) AP Chemistry. Period Date / / R e v i e w. 1. Consider the first ionization of sulfurous acid:

Thermodynamics. S (reactants) S S (products) AP Chemistry. Period Date / / R e v i e w. 1. Consider the first ionization of sulfurous acid: AP Chemistry Thermodynamics 1. Consider the first ionization of sulfurous acid: H 2SO 3(aq) H + (aq) + HSO 3 - (aq) Certain related thermodynamic data are provided below: H 2SO 3(aq) H + (aq) HSO 3 - (aq)

More information

Explorations in Thermodynamics: Calorimetry, Enthalpy & Heats of Reaction

Explorations in Thermodynamics: Calorimetry, Enthalpy & Heats of Reaction Explorations in Thermodynamics: Calorimetry, Enthalpy & Heats of Reaction Dena K. Leggett, Ph.D. and Jon H. Hardesty, Ph.D. Collin County Community College Dept. of Chemistry 1. Introduction: One of the

More information

Calorimetry: Determining the Heat of Fusion of Ice and the Heat of Vaporization of Liquid Nitrogen - Chemistry I Acc

Calorimetry: Determining the Heat of Fusion of Ice and the Heat of Vaporization of Liquid Nitrogen - Chemistry I Acc Calorimetry: Determining the Heat of Fusion of Ice and the Heat of Vaporization of Liquid Nitrogen - Chemistry I Acc O B J E C T I V E 1. Using a simple calorimeter, Determine the heat of fusion of ice

More information

Lab Session 9, Experiment 8: Calorimetry, Heat of Reaction

Lab Session 9, Experiment 8: Calorimetry, Heat of Reaction Lab Session 9, Experiment 8: Calorimetry, Heat of Reaction Specific heat is an intensive property of a single phase (solid, liquid or gas) sample that describes how the temperature of the sample changes

More information

Chemistry 151 Final Exam

Chemistry 151 Final Exam Chemistry 151 Final Exam Name: SSN: Exam Rules & Guidelines Show your work. No credit will be given for an answer unless your work is shown. Indicate your answer with a box or a circle. All paperwork must

More information

5.2. Determining Enthalpy of Reaction by Experiment. Specific Heat Capacity. 234 MHR Unit 3 Energy Changes and Rates of Reaction

5.2. Determining Enthalpy of Reaction by Experiment. Specific Heat Capacity. 234 MHR Unit 3 Energy Changes and Rates of Reaction In this section, you will 5.2 Section Preview/ Specific Expectations determine the heat that is produced by a reaction using a calorimeter, and use the data obtained to calculate the enthalpy change for

More information

q = (mass) x (specific heat) x T = m c T (1)

q = (mass) x (specific heat) x T = m c T (1) Experiment: Heat Effects and Calorimetry Heat is a form of energy, sometimes called thermal energy, which can pass spontaneously from an object at a high temperature to an object at a lower temperature.

More information

AP Practice Questions

AP Practice Questions 1) AP Practice Questions The tables above contain information for determining thermodynamic properties of the reaction below. C 2 H 5 Cl(g) + Cl 2 (g) C 2 H 4 Cl 2 (g) + HCl(g) (a) Calculate ΔH for

More information

Spontaneity of a Chemical Reaction

Spontaneity of a Chemical Reaction Spontaneity of a Chemical Reaction We have learned that entropy is used to quantify the extent of disorder resulting from the dispersal of matter in a system. Also; entropy, like enthalpy and internal

More information

States of Matter CHAPTER 10 REVIEW SECTION 1. Name Date Class. Answer the following questions in the space provided.

States of Matter CHAPTER 10 REVIEW SECTION 1. Name Date Class. Answer the following questions in the space provided. CHAPTER 10 REVIEW States of Matter SECTION 1 SHORT ANSWER Answer the following questions in the space provided. 1. Identify whether the descriptions below describe an ideal gas or a real gas. ideal gas

More information

2 Stoichiometry: Chemical Arithmetic Formula Conventions (1 of 24) 2 Stoichiometry: Chemical Arithmetic Stoichiometry Terms (2 of 24)

2 Stoichiometry: Chemical Arithmetic Formula Conventions (1 of 24) 2 Stoichiometry: Chemical Arithmetic Stoichiometry Terms (2 of 24) Formula Conventions (1 of 24) Superscripts used to show the charges on ions Mg 2+ the 2 means a 2+ charge (lost 2 electrons) Subscripts used to show numbers of atoms in a formula unit H 2 SO 4 two H s,

More information

87 16 70 20 58 24 44 32 35 40 29 48 (a) graph Y versus X (b) graph Y versus 1/X

87 16 70 20 58 24 44 32 35 40 29 48 (a) graph Y versus X (b) graph Y versus 1/X HOMEWORK 5A Barometer; Boyle s Law 1. The pressure of the first two gases below is determined with a manometer that is filled with mercury (density = 13.6 g/ml). The pressure of the last two gases below

More information

Exp 13 Volumetric Analysis: Acid-Base titration

Exp 13 Volumetric Analysis: Acid-Base titration Exp 13 Volumetric Analysis: Acid-Base titration Exp. 13 video (time: 47:17 minutes) Titration - is the measurement of the volume of a standard solution required to completely react with a measured volume

More information

Chemistry B11 Chapter 4 Chemical reactions

Chemistry B11 Chapter 4 Chemical reactions Chemistry B11 Chapter 4 Chemical reactions Chemical reactions are classified into five groups: A + B AB Synthesis reactions (Combination) H + O H O AB A + B Decomposition reactions (Analysis) NaCl Na +Cl

More information

Mr. Bracken. Multiple Choice Review: Thermochemistry

Mr. Bracken. Multiple Choice Review: Thermochemistry Mr. Bracken AP Chemistry Name Period Multiple Choice Review: Thermochemistry 1. If this has a negative value for a process, then the process occurs spontaneously. 2. This is a measure of how the disorder

More information

Name AP CHEM / / Collected AP Exam Essay Answers for Chapter 16

Name AP CHEM / / Collected AP Exam Essay Answers for Chapter 16 Name AP CHEM / / Collected AP Exam Essay Answers for Chapter 16 1980 - #7 (a) State the physical significance of entropy. Entropy (S) is a measure of randomness or disorder in a system. (b) From each of

More information

1. Balance the following equation. What is the sum of the coefficients of the reactants and products?

1. Balance the following equation. What is the sum of the coefficients of the reactants and products? 1. Balance the following equation. What is the sum of the coefficients of the reactants and products? 1 Fe 2 O 3 (s) + _3 C(s) 2 Fe(s) + _3 CO(g) a) 5 b) 6 c) 7 d) 8 e) 9 2. Which of the following equations

More information

Chapter 18 Homework Answers

Chapter 18 Homework Answers Chapter 18 Homework Answers 18.22. 18.24. 18.26. a. Since G RT lnk, as long as the temperature remains constant, the value of G also remains constant. b. In this case, G G + RT lnq. Since the reaction

More information

n molarity = M = N.B.: n = litres (solution)

n molarity = M = N.B.: n = litres (solution) 1. CONCENTRATION UNITS A solution is a homogeneous mixture of two or more chemical substances. If we have a solution made from a solid and a liquid, we say that the solid is dissolved in the liquid and

More information

Experiment 6 Coffee-cup Calorimetry

Experiment 6 Coffee-cup Calorimetry 6-1 Experiment 6 Coffee-cup Calorimetry Introduction: Chemical reactions involve the release or consumption of energy, usually in the form of heat. Heat is measured in the energy units, Joules (J), defined

More information

Name: Date: A) -156 kj/mol B) kj/mol C) -272 kj/mol D) -198 kj/mol E) -122 kj/mol

Name: Date: A) -156 kj/mol B) kj/mol C) -272 kj/mol D) -198 kj/mol E) -122 kj/mol Name: Date: 1. A coffee cup calorimeter containing 100.0 ml of concentrated HCl at 20.3 C. When 1.82 g Zn(s) is added, the temperature rises to 30.5 C. What is the heat of reaction per mol of reacted Zn?

More information

Thermochemistry. r2 d:\files\courses\1110-20\99heat&thermorans.doc. Ron Robertson

Thermochemistry. r2 d:\files\courses\1110-20\99heat&thermorans.doc. Ron Robertson Thermochemistry r2 d:\files\courses\1110-20\99heat&thermorans.doc Ron Robertson I. What is Energy? A. Energy is a property of matter that allows work to be done B. Potential and Kinetic Potential energy

More information

The first law: transformation of energy into heat and work. Chemical reactions can be used to provide heat and for doing work.

The first law: transformation of energy into heat and work. Chemical reactions can be used to provide heat and for doing work. The first law: transformation of energy into heat and work Chemical reactions can be used to provide heat and for doing work. Compare fuel value of different compounds. What drives these reactions to proceed

More information

CHEM 105 HOUR EXAM III 28-OCT-99. = -163 kj/mole determine H f 0 for Ni(CO) 4 (g) = -260 kj/mole determine H f 0 for Cr(CO) 6 (g)

CHEM 105 HOUR EXAM III 28-OCT-99. = -163 kj/mole determine H f 0 for Ni(CO) 4 (g) = -260 kj/mole determine H f 0 for Cr(CO) 6 (g) CHEM 15 HOUR EXAM III 28-OCT-99 NAME (please print) 1. a. given: Ni (s) + 4 CO (g) = Ni(CO) 4 (g) H Rxn = -163 k/mole determine H f for Ni(CO) 4 (g) b. given: Cr (s) + 6 CO (g) = Cr(CO) 6 (g) H Rxn = -26

More information

Enthalpy of Reaction and Calorimetry worksheet

Enthalpy of Reaction and Calorimetry worksheet Enthalpy of Reaction and Calorimetry worksheet 1. Calcium carbonate decomposes at high temperature to form carbon dioxide and calcium oxide, calculate the enthalpy of reaction. CaCO 3 CO 2 + CaO 2. Carbon

More information

Thermochemistry I: Endothermic & Exothermic Reactions

Thermochemistry I: Endothermic & Exothermic Reactions THERMOCHEMISTRY I 77 Thermochemistry I: Endothermic & Exothermic Reactions OBJECTIVES: Learn elementary concepts of calorimetry and thermochemistry Practice techniques of careful temperature, mass, and

More information

SUPPLEMENTARY TOPIC 3 ENERGY AND CHEMICAL REACTIONS

SUPPLEMENTARY TOPIC 3 ENERGY AND CHEMICAL REACTIONS SUPPLEMENTARY TOPIC 3 ENERGY AND CHEMICAL REACTIONS Rearranging atoms. In a chemical reaction, bonds between atoms in one or more molecules (reactants) break and new bonds are formed with other atoms to

More information

AP CHEMISTRY 2010 SCORING GUIDELINES

AP CHEMISTRY 2010 SCORING GUIDELINES 2010 SCORING GUIDELINES Question 2 (10 points) A student performs an experiment to determine the molar enthalpy of solution of urea, H 2 NCONH 2. The student places 91.95 g of water at 25 C into a coffee

More information

Chapter 6 Chemical Calculations

Chapter 6 Chemical Calculations Chapter 6 Chemical Calculations 1 Submicroscopic Macroscopic 2 Chapter Outline 1. Formula Masses (Ch 6.1) 2. Percent Composition (supplemental material) 3. The Mole & Avogadro s Number (Ch 6.2) 4. Molar

More information

CHEM 36 General Chemistry EXAM #1 February 13, 2002

CHEM 36 General Chemistry EXAM #1 February 13, 2002 CHEM 36 General Chemistry EXAM #1 February 13, 2002 Name: Serkey, Anne INSTRUCTIONS: Read through the entire exam before you begin. Answer all of the questions. For questions involving calculations, show

More information

Introductory Chemistry, 3 rd Edition Nivaldo Tro. Roy Kennedy Massachusetts Bay Community College Wellesley Hills, Maqqwertd ygoijpk[l

Introductory Chemistry, 3 rd Edition Nivaldo Tro. Roy Kennedy Massachusetts Bay Community College Wellesley Hills, Maqqwertd ygoijpk[l Introductory Chemistry, 3 rd Edition Nivaldo Tro Quantities in Car an octane and oxygen molecules and carbon dioxide and water Chemical Reactions Roy Kennedy Massachusetts Bay Community College Wellesley

More information

Chemistry 11 Some Study Materials for the Final Exam

Chemistry 11 Some Study Materials for the Final Exam Chemistry 11 Some Study Materials for the Final Exam Prefix Abbreviation Exponent giga G 10 9 mega M 10 6 kilo k 10 3 hecto h 10 2 deca da 10 1 deci d 10-1 centi c 10-2 milli m 10-3 micro µ 10-6 nano n

More information

Molecular Formula: Example

Molecular Formula: Example Molecular Formula: Example A compound is found to contain 85.63% C and 14.37% H by mass. In another experiment its molar mass is found to be 56.1 g/mol. What is its molecular formula? 1 CHAPTER 3 Chemical

More information

Thermodynamics explores the connection between energy and the EXTENT of a reaction but does not give information about reaction rates (Kinetics).

Thermodynamics explores the connection between energy and the EXTENT of a reaction but does not give information about reaction rates (Kinetics). Thermodynamics explores the connection between energy and the EXTENT of a reaction but does not give information about reaction rates (Kinetics). Rates of chemical reactions are controlled by activation

More information

7. 2. KOH (you need an acid or a base, this is a base) 8. 1. 76. All gold atoms have 79 protons and electrons, this is a +3 cation.

7. 2. KOH (you need an acid or a base, this is a base) 8. 1. 76. All gold atoms have 79 protons and electrons, this is a +3 cation. IB/SL Chemistry Name ANSWERS Test; Past Chemistry Regents Exams Most Frequently Missed Questions 1. 1. A HIGH PROBABLITY OF FINDING AN ELECTRON 2. 3. +8 (every atom of oxygen in the universe) 3. 2. LOW

More information

Module 5: Combustion Technology. Lecture 34: Calculation of calorific value of fuels

Module 5: Combustion Technology. Lecture 34: Calculation of calorific value of fuels 1 P age Module 5: Combustion Technology Lecture 34: Calculation of calorific value of fuels 2 P age Keywords : Gross calorific value, Net calorific value, enthalpy change, bomb calorimeter 5.3 Calculation

More information

APS Science Curriculum Unit Planner

APS Science Curriculum Unit Planner Grade Level/Subject APS Science Curriculum Unit Planner Enduring Understanding Chemistry Stage 1: Desired Results Topic 3: Kinetics: The Kinetic Theory can explain the phases of matter, the energetics

More information

Test 5 Review questions. 1. As ice cools from 273 K to 263 K, the average kinetic energy of its molecules will

Test 5 Review questions. 1. As ice cools from 273 K to 263 K, the average kinetic energy of its molecules will Name: Thursday, December 13, 2007 Test 5 Review questions 1. As ice cools from 273 K to 263 K, the average kinetic energy of its molecules will 1. decrease 2. increase 3. remain the same 2. The graph below

More information

A k 1. At equilibrium there is no net change in [A] or [B], namely d[a] dt

A k 1. At equilibrium there is no net change in [A] or [B], namely d[a] dt Chapter 15: Chemical Equilibrium Key topics: Equilibrium Constant Calculating Equilibrium Concentrations The Concept of Equilibrium Consider the reaction A k 1 k 1 B At equilibrium there is no net change

More information

Chapter 7: Chemical Equations. Name: Date: Period:

Chapter 7: Chemical Equations. Name: Date: Period: Chapter 7: Chemical Equations Name: Date: Period: 7-1 What is a chemical reaction? Read pages 232-237 a) Explain what a chemical reaction is. b) Distinguish between evidence that suggests a chemical reaction

More information

Review - After School Matter Name: Review - After School Matter Tuesday, April 29, 2008

Review - After School Matter Name: Review - After School Matter Tuesday, April 29, 2008 Name: Review - After School Matter Tuesday, April 29, 2008 1. Figure 1 The graph represents the relationship between temperature and time as heat was added uniformly to a substance starting at a solid

More information

Experiment 25: Calorimetry

Experiment 25: Calorimetry Aaron Bunch CHEM 111 Morning Lab 27 October 2014 Experiment 25: Calorimetry Conclusion: The unknown metal #14 has a specific heat of 0.36 J/g C; the heat of neutralization of HCl and NaOH is -53.0 kj/mol

More information

Chapter 13 Chemical Equilibrium. Equilibrium is Dynamic. The Equilibrium Constant. Equilibrium and Catalysts. Characteristics of Chemical Equilibrium

Chapter 13 Chemical Equilibrium. Equilibrium is Dynamic. The Equilibrium Constant. Equilibrium and Catalysts. Characteristics of Chemical Equilibrium Characteristics of Chemical Equilibrium John W. Moore Conrad L. Stanitski Peter C. Jurs http://academic.cengage.com/chemistry/moore Chapter 13 Chemical Equilibrium Many reactions fail to go to completion.

More information

Intermolecular Forces

Intermolecular Forces Intermolecular Forces: Introduction Intermolecular Forces Forces between separate molecules and dissolved ions (not bonds) Van der Waals Forces 15% as strong as covalent or ionic bonds Chapter 11 Intermolecular

More information

Chemical calculations

Chemical calculations Chemical calculations Stoichiometry refers to the quantities of material which react according to a balanced chemical equation. Compounds are formed when atoms combine in fixed proportions. E.g. 2Mg +

More information

Answers: Given: No. [COCl 2 ] = K c [CO][Cl 2 ], but there are many possible values for [CO]=[Cl 2 ]

Answers: Given: No. [COCl 2 ] = K c [CO][Cl 2 ], but there are many possible values for [CO]=[Cl 2 ] Chemical Equilibrium What are the concentrations of reactants and products at equilibrium? How do changes in pressure, volume, temperature, concentration and the use of catalysts affect the equilibrium

More information

CHEMICAL EQUILIBRIUM

CHEMICAL EQUILIBRIUM Chemistry 10 Chapter 14 CHEMICAL EQUILIBRIUM Reactions that can go in both directions are called reversible reactions. These reactions seem to stop before they go to completion. When the rate of the forward

More information

AP Chem Lab 2 Quiz #1 Calorimetry. Conceptual Understanding. Write complete sentences to show your understanding.

AP Chem Lab 2 Quiz #1 Calorimetry. Conceptual Understanding. Write complete sentences to show your understanding. AP Chem Lab 2 Quiz #1 Calorimetry Name Conceptual Understanding. Write complete sentences to show your understanding. Differentiate between kinetic energy and potential energy. Energy may be transferred

More information

Reading. Spontaneity. Monday, January 30 CHEM 102H T. Hughbanks

Reading. Spontaneity. Monday, January 30 CHEM 102H T. Hughbanks Thermo Notes #3 Entropy and 2nd Law of Thermodynamics Monday, January 30 CHEM 102H T. Hughbanks Reading You should reading Chapter 7. Some of this material is quite challenging, be sure to read this material

More information

Experiment 9: Enthalpy of Formation of Magnesium Oxide

Experiment 9: Enthalpy of Formation of Magnesium Oxide 1 Experiment 9: Enthalpy of Formation of Magnesium Oxide Objective: In this experiment, a simple calorimeter will be constructed and calibrated, and Hess law of constant heat summation will be used to

More information

CHEMISTRY STANDARDS BASED RUBRIC ATOMIC STRUCTURE AND BONDING

CHEMISTRY STANDARDS BASED RUBRIC ATOMIC STRUCTURE AND BONDING CHEMISTRY STANDARDS BASED RUBRIC ATOMIC STRUCTURE AND BONDING Essential Standard: STUDENTS WILL UNDERSTAND THAT THE PROPERTIES OF MATTER AND THEIR INTERACTIONS ARE A CONSEQUENCE OF THE STRUCTURE OF MATTER,

More information

The Mole Concept. A. Atomic Masses and Avogadro s Hypothesis

The Mole Concept. A. Atomic Masses and Avogadro s Hypothesis The Mole Concept A. Atomic Masses and Avogadro s Hypothesis 1. We have learned that compounds are made up of two or more different elements and that elements are composed of atoms. Therefore, compounds

More information

Unit 3 Notepack Chapter 7 Chemical Quantities Qualifier for Test

Unit 3 Notepack Chapter 7 Chemical Quantities Qualifier for Test Unit 3 Notepack Chapter 7 Chemical Quantities Qualifier for Test NAME Section 7.1 The Mole: A Measurement of Matter A. What is a mole? 1. Chemistry is a quantitative science. What does this term mean?

More information

Assessment Schedule 2015 Chemistry: Demonstrate understanding of bonding, structure, properties and energy changes (91164)

Assessment Schedule 2015 Chemistry: Demonstrate understanding of bonding, structure, properties and energy changes (91164) NCEA Level 2 Chemistry (91164) 2015 page 1 of 7 Assessment Schedule 2015 Chemistry: Demonstrate understanding of bonding, structure, properties and energy changes (91164) Evidence Statement Q Evidence

More information

Heat of Solution. Purpose To calculate the heat of solution for sodium hydroxide (NaOH) and ammonium nitrate (NH 4 NO 3 )

Heat of Solution. Purpose To calculate the heat of solution for sodium hydroxide (NaOH) and ammonium nitrate (NH 4 NO 3 ) Heat of Solution Purpose To calculate the heat of solution for sodium hydroxide (NaOH) and ammonium nitrate (NH 4 NO 3 ) Background For a given solute, the heat of solution is the change in enerrgy that

More information

5 Energetics. James Prescott Joule (1818 89) was devoted to making accurate measurements of heat. The SI unit of energy is named after him.

5 Energetics. James Prescott Joule (1818 89) was devoted to making accurate measurements of heat. The SI unit of energy is named after him. 5 Energetics All chemical reactions are accompanied by energy changes. Energy changes are vital. Our body s processes are dependent on the energy changes which occur during respiration, when glucose reacts

More information