If you need to reverse a reaction, the enthalpy is negated:

Size: px
Start display at page:

Download "If you need to reverse a reaction, the enthalpy is negated:"

Transcription

1 In the previous experiment you explored the heat of solution of potassium hydroxide. Using Hess s law, you will now use those results in conjunction with the data collected in this experiment to determine the enthalpy of neutralization for the reaction between potassium hydroxide (KOH) and hydrochloric acid (HCl) Prelaboratory Assignment Read this lab guide and Section 6.7 in your textbook. Then, complete the prelab assignment in Chem21. The prelab assignment is due at the beginning of lab on the day your lab meets Introduction Enthalpy is a state function, meaning the enthalpy for a process only depends on the initial and final states of the system. Hess s law states that when several reactions are added together, their enthalpies can be added together to give the enthalpy for the sum of the reactions. For example: A + B C H 1 C D + E H 2 A + B D + E H = H 1 + H 2 If you need to reverse a reaction, the enthalpy is negated: C A + B H = H 1 Finally, if you need to multiply a reaction by a coefficient, the enthalpy is also multiplied by the same coefficient: 3(A + B C) H = 3 H 1 In the previous experiment, you determined H soln, the enthalpy for the dissolution of KOH (Reaction 1, below). In this experiment, you will determine H neut, the enthalpy for the neutralization of solid KOH (Reaction 2, below). You will then combine these 1

2 values using Hess s law to calculate H for the neutralization of aqueous KOH with HCl (Reaction 3, below). Finally, you will perform Reaction 3 and compare your experimental result with the theoretical result you calculated Precautionary Measures KOH is a strong base and HCl is a strong acid. Both are extremely corrosive chemicals that will burn your skin and eat holes in your clothing. Wear your safety goggles at all times and wear gloves when handling solid KOH, KOH solutions, and HCl solutions. If small quantities of solid KOH, KOH solution or HCl solution are spilled on you, rinse the chemicals off for several minutes with a stream of cold water from the sink. Also inform your instructor right away. In the case of a small spill on a countertop, wipe up the chemicals with a paper towel, and rinse the area thoroughly with water. In the case of a larger spill, seek the assistance of your instructor Experimental In this experiment, you will be graded on your accuracy. Set up your lab notebook. You will be recording temperatures over time as you did in the previous experiment. This data should be recorded in a table. Insert a thermometer in a Styrofoam cup that has been placed on a magnetic stir plate. (Do not turn on the heater!) Also, put a magnetic stirbar in the cup. For each reaction you will start with a measured volume of hydrochloric acid solution in the Styrofoam cup. You will turn on the stirrer and establish a baseline temperature by recording the temperature of the solution (to the nearest tenth of a degree) every 15 seconds for approximately two minutes. You will then add a known mass of solid KOH or a known volume of KOH solution to the HCl solution and continue to record temperatures every 5 seconds in a table in your notebook until the temperature of the water remains the same for minutes or decreases for 5 measurements in a row. The initial temperature (T i) is the last baseline temperature reading before the KOH is added. The final temperature (T f ) is the highest temperature, not the last temperature reading recorded. Reaction 1: KOH(s) KOH(aq) Reaction 1 was completed during the last experiment, so we only need the data from that experiment for this part. You should have already recorded that data in your lab notebook as part of your prelaboratory assignment. 2

3 Reaction 2: KOH(s) + HCl(aq) H 2 O(l) + KCl(aq) Use a graduated cylinder to obtain approximately 100 ml of 1.5 M HCl solution. Record the exact volume and concentration, and then pour it into the cup. Establish a baseline temperature as described above. In the meantime, weigh between about 3 g of KOH into a weigh boat, being certain to record the exact mass of KOH. (Remove the weigh boat from the balance pan when adding KOH to avoid spills.) As quickly as possible, start timing, and add the KOH to the HCl solution. Record the temperature as described above. After recording the temperature, use litmus paper to determine whether your final solution is acidic or basic. Enter the result in your notebook and use that observation to determine which is the limiting reagent, KOH or HCl. Use tweezers to remove the stir bar, and pour the solution into an 800 ml beaker so you can dispose of it properly later. DO NOT POUR THE SOLUTION DOWN THE DRAIN. Rinse and dry your cup, stirbar, thermometer and weigh boat. Then, repeat this process so you will have two values for H neut to average together. Reaction 3: KOH(aq) + HCl(aq) H 2 O(l) + KCl(aq) Use a graduated cylinder to obtain approximately 50 ml of 1.5 M HCl solution. Record the exact volume and concentration, and then pour it into the cup. Establish a baseline temperature as described above. In the meantime, rinse and dry the graduated cylinder, and obtain about 50 ml of the 1 M KOH solution, being certain to record the concentration and the exact volume. As quickly as possible, start timing, and add this solution to the HCl solution. Record the temperature as described above. After recording the temperature, use litmus paper to determine whether your final solution is acidic or basic. Enter the result in your lab notebook and use that observation to determine which is the limiting reagent, KOH or HCl. Use tweezers to remove the stir bar, and pour the solution into an 800 ml beaker so you can dispose of it properly later. DO NOT POUR THE SOLUTION DOWN THE DRAIN. Rinse and dry your cup, stirbar, thermometer and weigh boat. Then, repeat this process so you will have two values for H to average together Hazardous Waste and Clean-up Hazardous Waste At the end of the lab, transfer all of your waste material to the provided receptacle in the hood. 3

4 Clean-up Dry your glassware (including your cup - don t throw it away!) and return it to your station. Then, wipe down your benchtop with a wet paper towel and dry it. Have your instructor check your station before your leave. BEFORE YOU LEAVE LAB: Tear out the carbon-copy pages of your notebook. Make sure your name, your partner s name and your section number are on each page. Staple these pages together and turn them in to your instructor Lab Assignment Enter all of your data, calculations and answers to questions in the Lab 10 Assignment in Chem21. You will need to refer to your notebook for this. The Assignment is due approximately 15 minutes before your next lab meeting Calculations The calculations are somewhat repetitive, so you may want to set up a table in your lab notebook to keep track of the results. Your table should look something like the table below. Reaction 2 Reaction 3 Trial 1 Trial 2 Trial 1 Trial 2 Volume of HCl Volume of KOH - - Total Volume Mass of water T q H2 O q rxn Mass of KOH - - Volume of KOH (L) - - Moles of KOH Volume of HCl (L) Moles of HCl Litmus Color Moles of Limiting Reagent H rxn Average H rxn For each trial of each reaction, calculate the total volume of the solution. 4

5 the mass of water g/ml.) (Assume this is the mass of the solution and the density is T (= highest temperature - initial temperature) q H2 O (= m H2 OC T where C = J/g C) q rxn (= q H2 O) the moles of KOH used. (When solid KOH is used, convert mass to moles using MW = g/mol. When aqueous KOH is used, use the molarity of the solution to convert volume to moles.) the moles of HCl. (Use volume and molarity.) which is the limiting reactant, HCl or KOH? (You should be able to tell by the number of moles of each that was used and your result should be confirmed by the litmus test.) H rxn (= q rxn /n where n is the number of moles of the limiting reagent.) Average the H rxn from each trial for each reaction. Use Hess s Law to calculate H for Reaction 3 using your values for H soln and H neut according to the formula you wrote in your prelab. Calculate the percent difference between the experimental H for Reaction 3 in your table and your calculated value above. Percent difference = calculated value experimental value experimental value 100% 5

Experiment #12. Enthalpy of Neutralization

Experiment #12. Enthalpy of Neutralization Experiment #12. Enthalpy of Neutralization Introduction In the course of most physical processes and chemical reactions there is a change in energy. In chemistry what is normally measured is ΔH (enthalpy

More information

CALORIMETRY. m = mass (in grams) of the solution C p = heat capacity (in J/g- C) at constant pressure T = change in temperature in degrees Celsius

CALORIMETRY. m = mass (in grams) of the solution C p = heat capacity (in J/g- C) at constant pressure T = change in temperature in degrees Celsius CALORIMETRY INTRODUCTION The heat evolved by a chemical reaction can be determined using a calorimeter. The transfer of heat or flow of heat is expressed as the change in Enthalpy of a reaction, H, at

More information

Thermodynamics Enthalpy of Reaction and Hess s Law

Thermodynamics Enthalpy of Reaction and Hess s Law P.O. Box 219 Batavia, Illinois 60510 1-800-452-1261 flinn@flinnsci.com Visit our website at: www.flinnsci.com 2003 Flinn Scientific, Inc. All Rights Reserved. Your Safer Source for Science Supplies Thermodynamics

More information

Chemistry CP Lab: Additivity of Heats of Reaction (Hess Law)

Chemistry CP Lab: Additivity of Heats of Reaction (Hess Law) Chemistry CP Lab: Additivity of Heats of Reaction (Hess Law) Name: Date: The formation or destruction of chemical bonds is always accompanied by an energy exchange between the reactant molecules and the

More information

8 Enthalpy of Reaction

8 Enthalpy of Reaction E x p e r i m e n t Enthalpy of Reaction Lecture and Lab Skills Emphasized Calculating the heat and enthalpy of reactions. Writing net ionic equations. Using Hess s law to determine the enthalpy of a reaction.

More information

THER Mo CHEMISTRY: HEAT OF Ne UTRALIZATION

THER Mo CHEMISTRY: HEAT OF Ne UTRALIZATION Experiment 11 Name: 42 THER Mo CHEMISTRY: HEAT OF Ne UTRALIZATION In this experiment, you will use calorimetry to experimentally determine the heat of neutralization of NaOH-HCl, or the enthalpy of the

More information

Ascorbic Acid Titration of Vitamin C Tablets

Ascorbic Acid Titration of Vitamin C Tablets Ascorbic Acid Titration of Vitamin C Tablets Part A. Preparation of Vitamin C Tablet Solutions 1. Obtain two vitamin C tablets. Place a plastic weighing boat on the balance, and press zero to tare the

More information

Name: Section: Score: /10 PRE LABORATORY ASSIGNMENT EXPERIMENT 7

Name: Section: Score: /10 PRE LABORATORY ASSIGNMENT EXPERIMENT 7 Name: Section: Score: /10 PRE LABORATORY ASSIGNMENT EXPERIMENT 7 1. Is the sign of Δ r H for an exothermic reaction positive or negative? Why? 2. When 4.21 grams of potassium hydroxide are added to 250.

More information

COPYRIGHT FOUNTAINHEAD PRESS

COPYRIGHT FOUNTAINHEAD PRESS Calorimetry: Heats of Solution Objective: Use calorimetric measurements to determine heats of solution of two ionic compounds. Materials: Solid ammonium nitrate (NH 4 NO 3 ) and anhydrous calcium chloride

More information

Determining the Enthalpy of a Chemical Reaction

Determining the Enthalpy of a Chemical Reaction Determining the Enthalpy of a Chemical Reaction Computer 13 All chemical reactions involve an exchange of heat energy; therefore, it is tempting to plan to follow a reaction by measuring the enthalpy change

More information

Thermodynamics. Equations to use for the calculations:

Thermodynamics. Equations to use for the calculations: Thermodynamics Introduction: Gibbs Free Energy, G, can be used to determine if a reaction is spontaneous or not. A negative value of G indicates that a given reaction is spontaneous at the measured conditions

More information

Thermochemistry: The Heat of Neutralization

Thermochemistry: The Heat of Neutralization Thermochemistry: The Heat of Neutralization Safety Solid NaOH is a severe contact hazard. Avoid touching it! HCl and NaOH solutions are both contact hazards. Wear goggles at all times since NaOH is a severe

More information

Chemistry 3202 Lab 6 Hess s Law 1

Chemistry 3202 Lab 6 Hess s Law 1 Chemistry 3202 Lab 6 Hess s Law 1 Lab 6 Hess's Law Introduction Chemical and physical changes are always accompanied by a change in energy. Energy changes may be observed by detecting heat flow between

More information

Thermodynamics. Equations to use for the calculations:

Thermodynamics. Equations to use for the calculations: Thermodynamics Introduction: Gibbs Free Energy, G, can be used to determine if a reaction is spontaneous or not. A negative value of G indicates that a given reaction is spontaneous at the measured conditions

More information

2. Synthesis of Aspirin

2. Synthesis of Aspirin This is a two-part laboratory experiment. In part one, you will synthesize (make) the active ingredient in aspirin through a reaction involving a catalyst. The resulting product will then be purified through

More information

EXPERIMENT A8: CALORIMETRY. Learning Outcomes. Introduction. Upon completion of this lab, the student will be able to:

EXPERIMENT A8: CALORIMETRY. Learning Outcomes. Introduction. Upon completion of this lab, the student will be able to: 1 EXPERIMENT A8: CALORIMETRY Learning Outcomes Upon completion of this lab, the student will be able to: 1) Measure the heat of a reaction under constant pressure conditions. 2) Calculate the enthalpy

More information

Name: Chemistry 103 Laboratory University of Massachusetts Boston HEATS OF REACTION PRELAB ASSIGNMENT

Name: Chemistry 103 Laboratory University of Massachusetts Boston HEATS OF REACTION PRELAB ASSIGNMENT Name: Chemistry 103 Laboratory University of Massachusetts Boston HEATS OF REACTION PRELAB ASSIGNMENT Chemical and physical changes usually involve the absorption or liberation of heat, given the symbol

More information

HEATS OF REACTION EXPERIMENT

HEATS OF REACTION EXPERIMENT 16 Text Reference Section 11.4 HEATS OF REACTION EXPERIMENT PURPOSE To measure the heats of reaction for three related exothermic reactions and to verify Hess s law of heat summation. Time Required 50

More information

ENTHALPY OF FORMATION OF MgO

ENTHALPY OF FORMATION OF MgO ENTHALPY OF FORMATION OF MgO ELECTRONIC LABORATORY NOTEBOOK (ELN) INSTRUCTIONS All work for this experiment must be recorded, attached, or answered in the ELN. Create a pre & inlab page in the Experiment

More information

Experiment 14 - Heats of Reactions

Experiment 14 - Heats of Reactions Experiment 14 - Heats of Reactions If a chemical reaction is carried out inside a calorimeter, the heat evolved or absorbed by the reaction can be determined. A calorimeter is an insulated container, and

More information

EXPERIMENT 9 ENTHALPY OF REACTION HESS S LAW

EXPERIMENT 9 ENTHALPY OF REACTION HESS S LAW EXPERIMENT 9 ENTHALPY OF REACTION HESS S LAW INTRODUCTION Chemical changes are generally accompanied by energy changes; energy is absorbed or evolved, usually as heat. Breaking chemical bonds in reactants

More information

Chem 2115 Experiment #7. Volumetric Analysis & Consumer Chemistry Standardization of an unknown solution, analysis of vinegar & antacid tablets

Chem 2115 Experiment #7. Volumetric Analysis & Consumer Chemistry Standardization of an unknown solution, analysis of vinegar & antacid tablets Chem 2115 Experiment #7 Volumetric Analysis & Consumer Chemistry Standardization of an unknown solution, analysis of vinegar & antacid tablets OBJECTIVE: The goals of this experiment are to learn titration

More information

How bad is that snack anyway?

How bad is that snack anyway? Physical Sciences 11 Experiment 1 How bad is that snack anyway? Monday, 2/10 Wednesday, 2/12 Science Center Room 117 Please read this entire document and complete the attached prelab before your lab. This

More information

Bellevue College CHEM& 121 Experiment: Stoichiometric Analysis of an Antacid 1

Bellevue College CHEM& 121 Experiment: Stoichiometric Analysis of an Antacid 1 Experiment: Stoichiometric Analysis of an Antacid 1 Introduction In this lab, you will use the concept of stoichiometry to solve two sequential problems. First, you will try to determine the products of

More information

Energy and Energy Conversion Minneapolis Community and Tech. College Principles of Chemistry 1 v q water = m water C water T water (Equation 1)

Energy and Energy Conversion Minneapolis Community and Tech. College Principles of Chemistry 1 v q water = m water C water T water (Equation 1) Energy and Energy Conversion Minneapolis Community and Tech. College Principles of Chemistry 1 v.6.13 Energy Energy is defined by most textbooks as the capacity to do work. However, the true usefulness

More information

HESS S LAW: ADDITIVITY OF HEATS OF REACTION

HESS S LAW: ADDITIVITY OF HEATS OF REACTION HESS S LAW: ADDITIVITY OF HEATS OF REACTION LAB THC 1.COMP From Chemistry with Computers, Vernier Software & Technology, 2000 INTRODUCTION In this experiment, you will use a Styrofoam-cup calorimeter to

More information

To use calorimetry results to calculate the specific heat of an unknown metal. To determine heat of reaction ( H) from calorimetry measurements.

To use calorimetry results to calculate the specific heat of an unknown metal. To determine heat of reaction ( H) from calorimetry measurements. Calorimetry PURPOSE To determine if a Styrofoam cup calorimeter provides adequate insulation for heat transfer measurements, to identify an unknown metal by means of its heat capacity and to determine

More information

Chemical Background Information: Magnesium reacts with oxygen in air to for magnesium oxide, according to equation 1.

Chemical Background Information: Magnesium reacts with oxygen in air to for magnesium oxide, according to equation 1. HESS S LAW LAB Pre lab assignment: You will need to complete the following parts prior to doing the lab: Title, Purpose, and Storyboard of the procedures for each part, Blank Data tables, and the Prelab

More information

The Enthalpies of Reactions

The Enthalpies of Reactions The Enthalpies of Reactions Collect 2 Styrofoam cups & a cup lid Digital thermometer Stop watch (from TA) Prepare 400 ml beaker 50 ml graduated cylinder * Take the warm water heated in hood (2015/09/20

More information

Percentage of Acetic Acid in Vinegar

Percentage of Acetic Acid in Vinegar Microscale Percentage of Acetic Acid in Vinegar When sweet apple cider is fermented in the absence of oxygen, the product is an acid, vinegar. Most commercial vinegars are made by fermentation, but some,

More information

Experiment #13. Enthalpy of Hydration of Sodium Acetate.

Experiment #13. Enthalpy of Hydration of Sodium Acetate. Experiment #13 Enthalpy of Hydration of Sodium Acetate Goal To determine the enthalpy (ΔH) for the following process: NaC 2 H 3 O 2 (s) + 3 H 2 O(l) à NaC 2 H 3 O 2 3H 2 O(s) Introduction Most chemical

More information

Chem 2115 Experiment #7. Volumetric Analysis & Consumer Chemistry Standardization of an unknown solution and the analysis of antacid tablets

Chem 2115 Experiment #7. Volumetric Analysis & Consumer Chemistry Standardization of an unknown solution and the analysis of antacid tablets Chem 2115 Experiment #7 Volumetric Analysis & Consumer Chemistry Standardization of an unknown solution and the analysis of antacid tablets OBJECTIVE: The goals of this experiment are to learn titration

More information

Reaction Stoichiometry

Reaction Stoichiometry Reaction Stoichiometry PURPOSE To determine the stoichiometry of acid-base reactions by measuring temperature changes which accompany them. GOALS To learn to use the MicroLab Interface. To practice generating

More information

Ascorbic Acid Titration of Vitamin C Tablets

Ascorbic Acid Titration of Vitamin C Tablets Ascorbic Acid Titration of Vitamin C Tablets Introduction This experiment illustrates how titration, the process of slowly adding one solution to another until the reaction between the two is complete,

More information

Additivity of Heats of Reaction: Hess s Law

Additivity of Heats of Reaction: Hess s Law Additivity of Heats of Reaction: Hess s Law Experiment In this experiment, you will use a Styrofoam-cup calorimeter to measure the heat released by three reactions. One of the reactions is the same as

More information

Experiment 12 Determination of an Enthalpy of Reaction, Using Hess s Law

Experiment 12 Determination of an Enthalpy of Reaction, Using Hess s Law Experiment 12 Determination of an Enthalpy of Reaction, Using Hess s Law Object: To measure the standard heat of formation, f, of MgO (s), and to become familiar with calorimetry as a toll for measuring

More information

Additivity of Heats of Reaction: Hess s Law

Additivity of Heats of Reaction: Hess s Law Additivity of Heats of Reaction: Hess s Law Experiment 21 In this experiment, you will use a Styrofoam-cup calorimeter to measure the heat released by three reactions. One of the reactions is the same

More information

Dr. White Chem 1B Saddleback College 1. Experiment 15 Thermodynamics of the Solution Process

Dr. White Chem 1B Saddleback College 1. Experiment 15 Thermodynamics of the Solution Process Dr. White Chem 1B Saddleback College 1 Experiment 15 Thermodynamics of the Solution Process Objectives To learn about the relationship between K and ΔG. To learn how the van't Hoff equation can be used

More information

Calorimetry Measurements of Fusion, Hydration and Neutralization - Hess Law

Calorimetry Measurements of Fusion, Hydration and Neutralization - Hess Law Calorimetry Measurements of Fusion, Hydration and Neutralization - Hess Law EXPERIMENT 9 Prepared by Edward L. Brown, Lee University and Verrill M. Norwood, Cleveland State Community College To become

More information

Thermochemistry: Calorimetry and Hess s Law

Thermochemistry: Calorimetry and Hess s Law Thermochemistry: Calorimetry and Hess s Law Some chemical reactions are endothermic and proceed with absorption of heat while others are exothermic and proceed with an evolution of heat. The magnitude

More information

(b) Write the chemical equation for the dissolution of NaOH in water.

(b) Write the chemical equation for the dissolution of NaOH in water. Making a Solution and Measuring ph Prelab Assignment Read the entire lab. Write an objective and any hazards associated with this lab in your laboratory notebook. Answer the following 6 questions in your

More information

Thermodynamics and the Solubility of Sodium Tetraborate Decahydrate

Thermodynamics and the Solubility of Sodium Tetraborate Decahydrate Thermodynamics and the Solubility of Sodium Tetraborate Decahydrate In this experiment you, as a class, will determine the solubility of sodium tetraborate decahydrate (Na 2 B 4 O 7 10 H 2 O or Na 2 [B

More information

Lab- Properties of Acids and Bases. Name. PSI Chemistry

Lab- Properties of Acids and Bases. Name. PSI Chemistry Lab- Properties of Acids and Bases PSI Chemistry Name Introduction Acids and bases are useful reagents in the chemistry laboratory and play an important role in biology and nature. What are acids and bases?

More information

Experiment 7: ACID-BASE TITRATION: STANDARDIZATION OF A SOLUTION

Experiment 7: ACID-BASE TITRATION: STANDARDIZATION OF A SOLUTION Experiment 7: ACID-BASE TITRATION: STANDARDIZATION OF A SOLUTION Purpose: Determine molarity of a solution of unknown concentration by performing acid-base titrations Performance Goals: Apply the concepts

More information

HESS S LAW: ADDITIVITY OF HEATS OF REACTION

HESS S LAW: ADDITIVITY OF HEATS OF REACTION HESS S LAW: ADDITIVITY OF HEATS OF REACTION From Chemistry with Calculators, Vernier Software & Technology In this experiment, you will use a Styrofoam-cup calorimeter to measure the heat released by three

More information

TRATION: ANALYSIS OF VINE

TRATION: ANALYSIS OF VINE Experiment 10 Name: 22 Ti TRATION: ANALYSIS OF VINE 31 Ga R In this experiment, you will learn the concept and technique of titration. You will determine the concentration of acetic acid in commercial

More information

Titration 3: NH 3 Titrated with HCl

Titration 3: NH 3 Titrated with HCl Titration 3: NH 3 Titrated with HCl Titration 1: Base is NH 3, Brom Blue in the indicator 1. Obtain about 60 ml of the standardized ( 0.1 M) HCl solution. CAUTION: Avoid spilling it on your skin or clothing.

More information

Enthalpy of Formation of Ammonium Chloride Version 6.2.5

Enthalpy of Formation of Ammonium Chloride Version 6.2.5 Enthalpy of Formation of Ammonium Chloride Version 6.2.5 Michael J. Vitarelli Jr. Department of Chemistry and Chemical Biology Rutgers University, 60 Taylor Road, Piscataway, NJ 08854 I. INTRODUCTION Enthalpy

More information

C q T q C T. Heat is absorbed by the system H > 0 endothermic Heat is released by the system H < 0 exothermic

C q T q C T. Heat is absorbed by the system H > 0 endothermic Heat is released by the system H < 0 exothermic PLEASE REORD ALL DATA DIRETLY INTO YOUR LAB NOTEBOOKS Introduction Heating a substance is one of the simplest processes carried out in the chemical laboratory, and is usually accompanied by a rise in the

More information

Modification of Procedure for Experiments 17 and 18. everything with distilled water and dry thoroughly. (Note: Do not use acetone to rinse cups.

Modification of Procedure for Experiments 17 and 18. everything with distilled water and dry thoroughly. (Note: Do not use acetone to rinse cups. Modification of Procedure for Experiments 17 and 18 I. Calorimeter Constant Obtain two polystyrene cups, a lid for one of the cups and a magnetic stirrer. Rinse everything with distilled water and dry

More information

c H2 O = J (g H 2 O)( C change)

c H2 O = J (g H 2 O)( C change) Calorimetry 1 CHM120 Introduction: Have you ever noticed the nutrition label located on the packaging of the food you buy? One of the first things listed on the label are the calories per serving. How

More information

CHEMISTRY 130 General Chemistry I. Thermochemistry

CHEMISTRY 130 General Chemistry I. Thermochemistry CHEMISTRY 130 General Chemistry I Thermochemistry The burning of a match, shown above [1], is a chemical reaction between oxygen and sulfur. [2] Intuitively, we know that this reaction releases heat enough

More information

Introduction. Objectives

Introduction. Objectives Experiment: Acids, Bases, and Buffers * Introduction Many common household solutions contain acids and bases. Acid-base indicators, such as litmus and red cabbage juice, turn different colors in acidic

More information

Chemical Reactions: Introduction to Reaction Types

Chemical Reactions: Introduction to Reaction Types Chemical Reactions: Introduction to Reaction Types **Lab Notebook** Record observations for all of the chemical reactions carried out during the lab in your lab book. These observations should include:

More information

DETERMINING AND USING H

DETERMINING AND USING H DETERMINING AND USING H INTRODUCTION CHANGES IN CHEMISTRY Chemistry is the science that studies matter and the changes it undergoes. Changes are divided into two categories: physical and chemical. During

More information

Titration with an Acid and a Base

Titration with an Acid and a Base Skills Practice Titration with an Acid and a Base Titration is a process in which you determine the concentration of a solution by measuring what volume of that solution is needed to react completely with

More information

Ascorbic Acid Titration of Vitamin C Tablets This lab will be completed individually! Make sure you come prepared!

Ascorbic Acid Titration of Vitamin C Tablets This lab will be completed individually! Make sure you come prepared! Ascorbic Acid Titration of Vitamin C Tablets This lab will be completed individually! Make sure you come prepared! This laboratory experiment has a formal report. Consult the guidelines for writing a formal

More information

Solution Calorimetry

Solution Calorimetry Experiment 7 Solution Calorimetry Prepared by Stephen E. Schullery and Ross S. Nord, Eastern Michigan University PURPOSE Measure the heats of two simple reactions and use Hess's Law to theoretically predict

More information

The Thermodynamics of the Solubility of Borax

The Thermodynamics of the Solubility of Borax Experiment 10 Pre-Lab Assignment Before coming to lab: Read the lab thoroughly. Answer the pre-lab questions that appear at the end of this lab exercise. The questions should be answered on a separate

More information

Read the lab thoroughly. Answer the pre-lab questions that appear at the end of this lab exercise.

Read the lab thoroughly. Answer the pre-lab questions that appear at the end of this lab exercise. Experiment 10 Stoichiometry- Gravimetric Analysis Pre-lab Assignment Read the lab thoroughly. Answer the pre-lab questions that appear at the end of this lab exercise. Purpose The purpose this experiment

More information

Heat of Combustion: Magnesium

Heat of Combustion: Magnesium Heat of Combustion: Magnesium Experiment 21 In Experiment 17, you learned about the additivity of reaction heats as you confirmed Hess s Law. In this experiment, you will use this principle as you determine

More information

Density of Aqueous Sodium Chloride Solutions

Density of Aqueous Sodium Chloride Solutions Experiment 3 Density of Aqueous Sodium Chloride Solutions Prepared by Ross S. Nord and Stephen E. Schullery, Eastern Michigan University PURPOSE Determine the concentration of an unknown sodium chloride

More information

experiment7 Explaining the difference between analyte and standard solutions. Know the definition of equivalence point.

experiment7 Explaining the difference between analyte and standard solutions. Know the definition of equivalence point. 93 experiment7 Determining an Unknown Concentration Understanding the concept of titration. LECTURE AND LAB SKILLS EMPHASIZED Explaining the difference between analyte and standard solutions. Know the

More information

Solution Calorimetry

Solution Calorimetry Experiment 7 Solution Calorimetry Prepared by Stephen E. Schullery and Ross S. Nord, Eastern Michigan University PURPOSE Measure the heats of two simple reactions and use Hess's Law to theoretically predict

More information

Lab #11: Heats of Reaction and Hess s Law Name: Lab Exercise. 10 points USE BLUE/BLACK INK!!!! Date: Hour:

Lab #11: Heats of Reaction and Hess s Law Name: Lab Exercise. 10 points USE BLUE/BLACK INK!!!! Date: Hour: Lab #11: Heats of Reaction and Hess s Law Name: _ Lab Exercise Chemistry II Partner: 10 points USE BLUE/BLACK INK!!!! Date: Hour: Goal: The goal of this lab is to determine the heat of reaction of burning

More information

The CCLI Initiative Computers in Chemistry Laboratory Instruction

The CCLI Initiative Computers in Chemistry Laboratory Instruction Experiment Determining the Coordination Number of Ni and Cu The CCLI Initiative Computers in Chemistry Laboratory Instruction by Enthalpy The objectives of this experiment are to... LEARNING OBJECTIVES

More information

Measuring Enthalpy Changes

Measuring Enthalpy Changes Measuring Enthalpy Changes PURPOSE To observe changes in enthalpy in chemical processes. GOALS To identify exothermic and endothermic processes. To relate enthalpy changes and entropy changes to changes

More information

Experiment 2 Heat of Combustion: Magnesium

Experiment 2 Heat of Combustion: Magnesium Experiment 2 Heat of Combustion: Magnesium Purpose Hess s Law states that when are going from a particular set of reactants to a particular set of products, the heat of reaction is the same whether the

More information

6 Acid Base Titration

6 Acid Base Titration E x p e r i m e n t Acid Base Titration Experiment : http://genchemlab.wordpress.com/-titration/ objectives To understand the concept of titration. To explain the difference between the analyte and standard

More information

Acid-Base Titration. Evaluation copy

Acid-Base Titration. Evaluation copy Acid-Base Titration Computer 7 A titration is a process used to determine the volume of a solution that is needed to react with a given amount of another substance. In this experiment, your goal is to

More information

The periodic table is the most recognized symbol in chemistry across the world. It is a valuable tool that allows scientists not only to classify the

The periodic table is the most recognized symbol in chemistry across the world. It is a valuable tool that allows scientists not only to classify the The periodic table is the most recognized symbol in chemistry across the world. It is a valuable tool that allows scientists not only to classify the elements but also to explain and predict their properties.

More information

Acidity of Beverages Lab

Acidity of Beverages Lab Acidity of Beverages Lab Name: Introduction: Common beverages may be either acidic or basic. Fruit juices, for example, get their sweet taste from sugars and their sour or tart taste from weak acids such

More information

Experiment 6: Using Calorimetry to Determine the Enthalpy of Formation of Magnesium Oxide

Experiment 6: Using Calorimetry to Determine the Enthalpy of Formation of Magnesium Oxide Experiment 6: Using Calorimetry to Determine the Enthalpy of Formation of Magnesium Oxide Reading: Chapter sections 5.4 5.7 of your textbook and this lab handout. Ongoing Learning Goals: To use a scientific

More information

Experiment 13H THE REACTION OF RED FOOD COLOR WITH BLEACH 1

Experiment 13H THE REACTION OF RED FOOD COLOR WITH BLEACH 1 Experiment 13H 08/03/2017 AHRM THE REACTION OF RED FOOD COLOR WITH BLEACH 1 PROBLEM: Determine the rate law for the chemical reaction between FD&C Red Dye #3 and sodium hypochlorite. LEARNING OBJECTIVES:

More information

Acid Base Titration Experiment ACID - BASE TITRATION LAB

Acid Base Titration Experiment ACID - BASE TITRATION LAB ACID - BASE TITRATION LAB MATERIALS and CHEMICALS Burette 50 ml Burette clamp Ring stand Stirring rod Plastic funnel Beakers (50 ml, 100 ml, 400 ml) Graduated cylinder (25 ml, 50 ml) 0.10 M NaOH 0.10 M

More information

CHEM 132 Lab 11 Western Carolina University

CHEM 132 Lab 11 Western Carolina University Name Lab Section Chemistry 132 Lab 11 How Effective is Your Antacid? Prelaboratory Exercise 1. How many grams of NaOH will you need to make 250 of 0.5 M NaOH solution? 2. What is the purpose of the first,

More information

Density of Aqueous Sodium Chloride Solutions

Density of Aqueous Sodium Chloride Solutions Experiment 3 Density of Aqueous Sodium Chloride Solutions Prepared by Ross S. Nord and Stephen E. Schullery, Eastern Michigan University PURPOSE Determine the concentration of an unknown sodium chloride

More information

AP Chemistry: Designing an Effective Hand Warmer Student Guide INTRODUCTION

AP Chemistry: Designing an Effective Hand Warmer Student Guide INTRODUCTION AP Chemistry: Designing an Effective Hand Warmer Student Guide INTRODUCTION AP and the Advanced Placement Program are registered trademarks of the College Entrance Examination Board. The activity and materials

More information

Synthesis of Benzoic Acid

Synthesis of Benzoic Acid E x p e r i m e n t 5 Synthesis of Benzoic Acid Objectives To use the Grignard reagent in a water free environment. To react the Grignard reagent with dry ice, CO 2(s). To assess the purity of the product

More information

Lab #5 - Limiting Reagent

Lab #5 - Limiting Reagent Objective Chesapeake Campus Chemistry 111 Laboratory Lab #5 - Limiting Reagent Use stoichiometry to determine the limiting reactant. Calculate the theoretical yield. Calculate the percent yield of a reaction.

More information

Lab 5 Enthalpy of Solution Formation

Lab 5 Enthalpy of Solution Formation Chemistry 3202 Lab 5 Enthalpy of Solution Formation Page 1 of 9 Lab 5 Enthalpy of Solution Formation Introduction This lab activity will introduce you to the measurement of energy change associated with

More information

Part II. Cu(OH)2(s) CuO(s)

Part II. Cu(OH)2(s) CuO(s) The Copper Cycle Introduction In this experiment, you will carry out a series of reactions starting with copper metal. This will give you practice handling chemical reagents and making observations. It

More information

In fact, we are going to be sneaky and use Hess s Law to determine the heat of magnesium combustion indirectly. Go to the website:

In fact, we are going to be sneaky and use Hess s Law to determine the heat of magnesium combustion indirectly. Go to the website: Chemistry 161 Please prepare your notebook though the data tables before class on Wednesday, October 27. Write an abstract and place it at the front of your individual report. The abstract and the report

More information

25. Qualitative Analysis 2

25. Qualitative Analysis 2 25. Qualitative Analysis 2 This experiment uses a series of wet chemistry analytical tests to determine the functional group present in a series of known and an unknown compound. Each student receives

More information

RATE LAW DETERMINATION OF CRYSTAL VIOLET HYDROXYLATION

RATE LAW DETERMINATION OF CRYSTAL VIOLET HYDROXYLATION Rate Law Determination of Crystal Violet Hydroxylation Revised 10/21/14 RATE LAW DETERMINATION OF CRYSTAL VIOLET HYDROXYLATION Adapted from "Chemistry with Computers" Vernier Software, Portland OR, 1997

More information

Calorimetery and Hess s Law

Calorimetery and Hess s Law Calorimetery and Hess s Law Overview: Calorimetry is the technique used to measure the heat required or evolved during a chemical reaction. Heat has units of joules, so one might expect to be using a joule

More information

Solvation and Freezing Point Depression

Solvation and Freezing Point Depression Experiment 4 Solvation and Freezing Point Depression Prepared by Ross S. Nord, Eastern Michigan University PURPOSE To investigate the solvation process, measure freezing-point depression, and determine

More information

Ascorbic Acid Titration of Vitamin C Tablets

Ascorbic Acid Titration of Vitamin C Tablets Ascorbic Acid Titration of Vitamin C Tablets Introduction This experiment illustrates how titration, the process of slowly adding one solution to another until the reaction between the two is complete,

More information

3. The hypothesis can then be tested by experiments designed to collect more data about the problem.

3. The hypothesis can then be tested by experiments designed to collect more data about the problem. University of Puget Sound Department of Chemistry Experiment 1 Chem 110 OBSERVATIONS-DESCRIBING WHAT CAN BE SEEN LABORATORY OBJECTIVES AND ASSESSMENTS 1. Be conversant in the use of laboratory notebooks

More information

Thermochemistry. Introduction. Pre-lab. Safety

Thermochemistry. Introduction. Pre-lab. Safety Introduction Thermochemistry All chemical reactions and phase changes involve energy. One form of energy is heat: when a change in the energy of a system results in a temperature difference, we say that

More information

Experiment 20-Acid-Base Titration: Standardization of KOH and Determination of the Molarity and/or Percent Composition of an Acid Solution

Experiment 20-Acid-Base Titration: Standardization of KOH and Determination of the Molarity and/or Percent Composition of an Acid Solution Experiment 20-Acid-Base Titration: Standardization of KOH and Determination of the Molarity and/or Percent Composition of an Acid Solution In this experiment, you will determine the molarity and percent

More information

RATE LAW DETERMINATION OF CRYSTAL VIOLET HYDROXYLATION

RATE LAW DETERMINATION OF CRYSTAL VIOLET HYDROXYLATION Rate Law Determination of Crystal Violet Hydroxylation Revised 5/22/12 RATE LAW DETERMINATION OF CRYSTAL VIOLET HYDROXYLATION Adapted from "Chemistry with Computers" Vernier Software, Portland OR, 1997

More information

POGIL LAB EXERCISE 15 HOW DO YOU STANDARDIZE AN ACID AND BASE?

POGIL LAB EXERCISE 15 HOW DO YOU STANDARDIZE AN ACID AND BASE? POGIL LAB EXERCISE 15 HOW DO YOU STANDARDIZE AN ACID AND BASE? POGIL LAB 15 Page 1 of 10 Each member should assume his or her role at this time. The new manager takes charge of the POGIL folder and hands

More information

THE THERMODYNAMICS OF POTASSIUM NITRATE DISSOLVING IN WATER V010516

THE THERMODYNAMICS OF POTASSIUM NITRATE DISSOLVING IN WATER V010516 THE THERMODYNAMICS OF POTASSIUM NITRATE DISSOLVING IN WATER V010516 OBJECTIVE The ΔG, ΔH and ΔS of the potassium nitrate (KNO3) dissolving reaction will be determined by measuring the equilibrium constant

More information

Experiment #10: Analysis of Antacids

Experiment #10: Analysis of Antacids Experiment #10: Analysis of Antacids Purpose: In this experiment you will prepare one solution that is approximately 0.1 M NaOH. Then you will standardize this solution, which means that you will experimentally

More information

STATES OF MATTER INTRODUCTION

STATES OF MATTER INTRODUCTION STATES OF MATTER INTRODUCTION In studying chemical reactions, we talk in terms of interactions between molecules, atoms, and electrons. However, in order to understand chemical changes, we must first have

More information

EXPERIMENT 5 ACID-BASE TITRATION

EXPERIMENT 5 ACID-BASE TITRATION EXPERIMENT 5 ACID-BASE TITRATION INTRODUCTION Much of chemistry and biology is concerned with the behavior of acids and bases. Acids and bases are participants in many reactions in nature, and many reactions

More information

Titration of an Unknown Acid

Titration of an Unknown Acid Experiment 6 Titration of an Unknown Acid Prepared by Stephen E. Schullery and Ross Nord, Eastern Michigan University PURPSE To determine the apparent molar mass of an unknown monoprotic acid by titrating

More information

Experiment #7. Titration of Vinegar

Experiment #7. Titration of Vinegar Experiment #7. Titration of Vinegar Goals 1. To determine the mass percent of acetic acid in a solution via titration. 2. To master the technique of titration. Introduction Vinegar is a common household

More information

NaOH (aq) + HCl (aq) NaCl (aq) + H 2 O (l)

NaOH (aq) + HCl (aq) NaCl (aq) + H 2 O (l) EXPERIMENT 21 Molarity of a Hydrochloric Acid Solution by Titration INTRODUCTION Volumetric analysis is a general term meaning any method in which a volume measurement is the critical operation; however,

More information