EXPERIMENT 2 Stoichiometry. Introduction

Size: px
Start display at page:

Download "EXPERIMENT 2 Stoichiometry. Introduction"

Transcription

1 EXPERIMENT 2 Stoichiometry Introduction Stoichiometry is the study of the quantitative relationships in chemical reactions. By studying stoichiometry, you can calculate the quantity of reactants that will be consumed in a chemical reaction, and the amount of product produced. Consider the reaction of vinegar with baking soda. As you may know, this reaction produces carbon dioxide gas which bubbles out of the vinegar. But if you want to know how much gas would be produced from combining a teaspoon of baking soda with a cup of vinegar, you would need to consider the stoichiometry of the reaction. Stoichiometry answers questions about chemical reactions dealing with how much and how many. In the first part of this experiment you will investigate the reaction of copper metal with oxygen in the air. Using stoichiometry, you can predict the amount of copper oxide (CuO) that could be produced if all the copper would react. However, when you perform the reaction yourself, you will discover that only some of the copper reacts to form black copper oxide. A stoichiometric calculation will allow you to determine the amount of copper oxide produced and the amount of unreacted copper remaining. In the second part of the experiment, you will use the techniques learned in the first part to investigate the chemical composition of an unknown compound. The solid compound will contain a certain quantity of water trapped inside it, and your task will be to calculate the amount of water it contains. Based on the amount of water released, you should be able to identify your unknown compound as one of the three possible compounds described in the experiment. You will need to make stoichiometric calculations in order to find out how much water should be released by each of the three unknown compounds, and compare that result with the amount of water actually released by your compound. Discussion Investigation of a Copper Reaction When heated in the presence of oxygen in the air, copper metal reacts to form copper oxide, CuO: 2 Cu (s) + O 2 (g) 2 CuO (s) Because only the surface of the copper metal will react to form copper oxide, you will use finely powdered copper in order to maximize its surface area. You will heat the copper powder in a crucible, which is a small thimble-shaped porcelain container used to heat substances to high temperatures. By heating the copper in a crucible using an intense gas flame from a Bunsen burner, you will be able to make much of the copper react to form copper oxide. However, despite the use of fine copper powder, some of the copper will not be exposed to oxygen in the air, and hence will remain unreacted. It is often the case that chemical reactions will not proceed entirely to completion, and this copper reaction is an example of such a reaction. With such a reaction, the amount of product Experiment 2 1

2 actually formed will be less than what could theoretically be produced in ideal circumstances. The amount of product formed is often reported in terms of a percent yield. The percent yield for a given reaction is defined as: mass of product formed precent yield 100 % theoretical maximum mass of product In this experiment, as the copper reacts to form copper oxide, the mass of the contents of the crucible will increase. This mass increase will correspond to the mass of oxygen consumed during the reaction. A stoichiometric calculation will enable you to determine the mass of copper oxide actually produced based on the mass of oxygen in the final product. The theoretical maximum mass of copper oxide can be calculated using stoichiometry based on the amount of copper used in the reaction. By comparing the mass of copper oxide actually produced with this theoretical amount, you can calculate the percent yield for your reaction. You would hope to get 100% yield in every chemical reaction, but in reality a perfect yield is rarely attained. Investigation of a Hydrated Salt At one time, you may have seen simple humidity indicators that change color to indicate the amount of water in the air. Or perhaps you have seen clothes that change color when wet, or children s bath toys that behave similarly. These items all depend on substances known as hydrated salts. A hydrated salt is a solid substance that contains water bound within the solid. For instance, the natural mineral bieberite has the formula CoSO 4 7H 2 O. This means that, for every atom of cobalt in the solid, there are 7 molecules of water also trapped within the solid. By heating the solid, the trapped water molecules can be released as water vapor: CoSO 4 7H 2 O (s) CoSO 4 (s) + 7 H 2 O (g) Note that the resulting solid will weigh less due to the water lost in the process. The release of the bound water is often accompanied by a color change. In the above example, the hydrated salt CoSO 4 7H 2 O is red-pink, while the anhydrous ( no water ) salt CoSO 4 is dark blue. These types of substances can be used to indicate the ambient humidity, because they will release water in dry environments and absorb water in moist environments, changing color in the process. In the second part of the experiment, you will be given one of the following hydrated salts, but will not be told which one you have: CuSO 4 5H 2 O CuCl 2 2H 2 O CoCl 2 6H 2 O Your task will be to remove all the water from your hydrated salt, determine how much water was removed, and thus discover which of the unknown salts you were given. You will report the quantity of water removed in terms of the ratio of moles of water released per mole of anhydrous salt. For instance, if your salt were CuSO 4 5H 2 O, you would expect to report that 5 moles of water were released per mole of anhydrous CuSO 4. In addition, you should observe any color changes during the course of the reaction. As described above, these color changes will indicate the progress of the reaction. Experiment 2 2

3 Procedure In this experiment you will work in partners. One partner will perform the copper experiment, while the other will independently perform the experiment with the hydrated salt. At the conclusion of the experiment you will swap data and discuss your observations and conclusions. Waste Disposal All waste produced in this experiment will be solid waste. Solid waste must be kept dry in order to dispose of it properly. After you are finished with the substances in your crucible, scrape the solid product into the container in the waste hood. Place the empty crucible in the appropriate dirty glassware container. Remember, do not use water to rinse the waste out of the crucibles. Use of the Crucible The crucible is a thin, porcelain container designed to withstand high temperatures. We will be heating the crucible using the gas flame of a Bunsen burner. Place a ceramic triangle on a metal tripod or ring stand. Obtain a crucible from the center bench, making sure it is not cracked, and place the crucible on the ceramic triangle. Connect a Bunsen burner to the gas outlet with a rubber hose and have your TF come and verify your setup. Your TF will show you how to light the burner and adjust the flame. The blue cone at the center of the burner flame should not be taller than one inch. Experiment 2 3

4

5 TF: 1/4 Name: Investigation of a Copper Reaction Data, Observations, and Notes First, take a clean, dry crucible from the center lab bench, bring it to the balance, and weigh the empty crucible. Using the analytical balance, weigh out approximately 1 gram of the copper powder. Add this powder to the empty crucible, and weigh the filled crucible. Return the crucible to the burner flame, and heat the copper powder. Do not heat the crucible so intensely that it glows red hot. Periodically remove the crucible from the flame and gently tap it against the benchtop in order to mix up the copper. While the crucible is away from the flame, note the color of the contents. Continue heating for at least 25 minutes, or until no more color change is observed. Mass of empty crucible: Mass: Mass of crucible with copper before heating: Mass: Color changes observed: Using the crucible tongs, carefully set the crucible aside to cool. When it has reached room temperature, weigh the crucible and its contents on an analytical balance. Final mass of crucible with product: Mass: Experiment 2 5

6 2/4 Investigation of a Hydrated Salt Data, Observations, and Notes This part of the experiment is performed very much like the copper reaction. In your prelab report, you will have to write out a detailed procedure. Your task will be to determine the mass of water released by heating one of the following hydrated salts: CuSO 4 5H 2 O, CuCl 2 2H 2 O, CoCl 2 6H 2 O. You will not know which of the salts you are heating, but should be able to deduce this from your final calculations. As part of your prelab, write up an appropriate data table in this space that you can use while performing the laboratory experiment. Don t forget to leave space in which to note the observed color changes. Here are some helpful hints for designing a successful procedure: You will be able to grind the sample into a fine powder using a mortar and pestle. Heat the compounds very gently. If the compound starts to turn brownish-black, gives off green gases, or starts to bubble and boil, then it is being overheated. Record all color changes observed for the compounds as they are heated. One of the compounds should exhibit more than one color change due to the formation of an intermediate stable hydrate with 2 moles of water per mole of anhydrous salt. The colors of the three anhydrous salts, in no particular order, are light blue, greenish-white, and yellow-brown. Once your entire sample has reached one of these colors, you should stop heating in order to avoid overheating. Experiment 2 6

7 TF: 3/4 Name: Lab Report Results 1. Determine the mass of CuO which was produced in the copper reaction, and calculate the percent yield of this reaction. Mass of CuO: Percent yield: 2. Calculate the mass of water released from the hydrated salt. Mass of water: 3. Determine the ratio of moles of water to moles of anhydrous salt assuming the unknown salt is CuSO 4. Ratio: Repeat this calculation assuming the salt is CuCl 2. Ratio: Repeat this calculation assuming the salt is CoCl 2. Ratio: 4. What is the most likely identity of your hydrated salt? Experiment 2 7

8

9 TF: 4/4 Name: Prelab 1. Provide a detailed procedure for determining the mass of water released upon heating a hydrated salt. Be sure you write up a data table in the appropriate space on that page of the experiment. 2. One student weighed gram of copper powder into a crucible and heated it to produce copper oxide. He was able to obtain only a 15% yield. What was the total mass of the crucible contents (CuO plus unreacted Cu) after the reaction? Mass of contents: 3. Another student heated gram of a red-pink hydrated salt until all the water had been removed. She was left with grams of a dark blue solid. Is it possible that the hydrated salt was bieberite, CoSO 4 7H 2 O? Why or why not? Calculations should be shown Provide a list of all the chemicals and equipment needed for this experiment. Be concise. Experiment 2 9

Percent Composition of Hydrates

Percent Composition of Hydrates Name Class Date Percent Composition of Hydrates You are a research chemist working for a company that is developing a new chemical moisture absorber and indicator. The company plans to seal the moisture

More information

The Formula Of A Compound

The Formula Of A Compound The Formula Of A Compound Introduction: A compound is a distinct substance composed of two or more elements chemically combined in fixed proportions. Atoms of the elements in a compound are combined in

More information

EXPERIMENT 3: DETERMINATION OF AN EMPIRICAL FORMULA

EXPERIMENT 3: DETERMINATION OF AN EMPIRICAL FORMULA EXPERIMENT 3: DETERMINATION OF AN EMPIRICAL FORMULA PURPOSE To find the empirical formula of a product based on experimental data. To determine the percentage of water of hydration in an unknown salt.

More information

Percent Composition of a Hydrate

Percent Composition of a Hydrate Chem 110 Lab Percent Composition of a Hydrate Clark College Percent composition will be discussed in your text, lecture and in lab. This concept is often used to determine how many grams of an element

More information

DETERMINATION of the EMPIRICAL FORMULA

DETERMINATION of the EMPIRICAL FORMULA DETERMINATION of the EMPIRICAL FORMULA One of the fundamental statements of the atomic theory is that elements combine in simple whole number ratios. This observation gives support to the theory of atoms,

More information

Determination of the Empirical Formula of Magnesium Oxide

Determination of the Empirical Formula of Magnesium Oxide Determination of the Empirical Formula of Magnesium Oxide GOAL AND OVERVIEW The quantitative stoichiometric relationships governing mass and amount will be studied using the combustion reaction of magnesium

More information

Option 2 will react tin with nitric acid to form a tin nitrate then the compound will be decomposed, by heating, to an oxide of tin.

Option 2 will react tin with nitric acid to form a tin nitrate then the compound will be decomposed, by heating, to an oxide of tin. EMPIRICAL FORMULA OF A COMPOUND 2009, 1986 by David A. Katz. All Rights reserved. Reproduction permitted for education use provided original copyright is included. OBJECTIVE In this experiment, a compound

More information

Determination of an Empirical Formula and % Composition

Determination of an Empirical Formula and % Composition Chem 110 Lab Clark College Determination of an Empirical Formula and % Composition Percent composition will be discussed in your text, lecture and in lab. This concept is often used to determine how many

More information

LAB SEVEN. Carbonate to Halide Conversion

LAB SEVEN. Carbonate to Halide Conversion Name Lab Partner(s) Section Date: Carbonate to Halide Conversion Objective The theoretical yield of the reaction product and the ratio of products to reactants will be predicted using the Law of Conservation

More information

HYDRATES 2009 by David A. Katz. All Rights reserved. Reproduction permitted for education use provided original copyright is included.

HYDRATES 2009 by David A. Katz. All Rights reserved. Reproduction permitted for education use provided original copyright is included. HYDRATES 2009 by David A. Katz. All Rights reserved. Reproduction permitted for education use provided original copyright is included. OBJECTIVE In this experiment, the properties of a hydrated compound

More information

Carbonate to Halide Conversion

Carbonate to Halide Conversion Conversion Objective The theoretical yield of the reaction product and the ratio of products to reactants will be predicted using the Law of Conservation of Matter and the Law of Definite Composition.

More information

Properties of Hydrates Prelab. 3. Give the chemical formula for copper(ii) nitrate pentahydrate.

Properties of Hydrates Prelab. 3. Give the chemical formula for copper(ii) nitrate pentahydrate. Properties of Hydrates Prelab Name Total /10 SHOW ALL WORK NO WORK = NO CREDIT 1. What is the purpose of this experiment?. What is the definition of a hydrate? 3. Give the chemical formula for copper(ii)

More information

Austin Peay State University Department of Chemistry CHEM 1111. Copper Cycle

Austin Peay State University Department of Chemistry CHEM 1111. Copper Cycle Cautions Nitric acid and sulfuric acid are toxic and oxidizers and may burn your skin. Nitrogen dioxide gas produced is hazardous if inhaled. Sodium hydroxide is toxic and corrosive and will cause burns

More information

EXPERIMENT 7 Reaction Stoichiometry and Percent Yield

EXPERIMENT 7 Reaction Stoichiometry and Percent Yield EXPERIMENT 7 Reaction Stoichiometry and Percent Yield INTRODUCTION Stoichiometry calculations are about calculating the amounts of substances that react and form in a chemical reaction. The word stoichiometry

More information

WATER OF HYDRATION EXPERIMENT 7

WATER OF HYDRATION EXPERIMENT 7 WATER OF HYDRATION EXPERIMENT 7 OBJECTIVE The objective of this experiment is to determine the percentage of water in a hydrated salt of both known and unknown formulas. The experimental results will be

More information

Experiment 7 GRAVIMETRIC ANALYSIS OF A TWO COMPONENT MIXTURE

Experiment 7 GRAVIMETRIC ANALYSIS OF A TWO COMPONENT MIXTURE Purpose Experiment 7 GRAVIMETRIC ANALYSIS OF A TWO COMPONENT MIXTURE The purpose of the experiment is to determine the percent composition by mass of a two component mixture made up of NaHCO 3 and Na 2

More information

CSUS Department of Chemistry Experiment 2 Chem. 1A

CSUS Department of Chemistry Experiment 2 Chem. 1A Name: Lab Section: EXPERIMENT 2: HYDRATE PRE LABORATORY ASSIGNMENT Score: /10 (To be completed prior to lab, read the experiment before attempting) 1. A student obtains the following data: Mass of test

More information

Lab #1: Determining the Empirical Formula of a Compound

Lab #1: Determining the Empirical Formula of a Compound Ms. Sonderleiter AP Chemistry Name: Date: Lab #1: Determining the Empirical Formula of a Compound Background: How did early chemists ever manage to determine the chemical formulas of compounds? What kind

More information

SUPPLEMENTARY MATERIAL

SUPPLEMENTARY MATERIAL SUPPLEMENTARY MATERIAL (Student Instructions) Determination of the Formula of a Hydrate A Greener Approach Objectives To experimentally determine the formula of a hydrate salt. To learn to think in terms

More information

Properties of Matter and Density

Properties of Matter and Density Cautions Flames will be used and some of the chemicals will have odors and may stain your hands or clothes if you come into direct contact with them. Purpose In this experiment you will characterize common

More information

What is a Chemical Reaction?

What is a Chemical Reaction? Lab 8 Name What is a Chemical Reaction? Macroscopic Indications and Symbolic Representations Pre-Lab Assignment This written pre-lab is worth 25% (5 POINTS) of your lab report grade and must be turned

More information

Chemistry 1215 Experiment #9 Copper and its Compounds

Chemistry 1215 Experiment #9 Copper and its Compounds Chemistry 1215 Experiment #9 Copper and its Compounds Objective The objective of this experiment is to take a piece of copper as efficiently as possible through a series of chemical reactions. The final

More information

STOICHIOMETRY: The Reaction of Iron with Copper (II) Sulfate

STOICHIOMETRY: The Reaction of Iron with Copper (II) Sulfate STOICHIOMETRY: The Reaction of Iron with Copper (II) Sulfate Introduction In this experiment we will use stoichiometric principles to deduce the appropriate equation for the reaction between metallic iron

More information

The Empirical Formula of a Compound

The Empirical Formula of a Compound The Empirical Formula of a Compound Lab #5 Introduction A look at the mass relationships in chemistry reveals little order or sense. The ratio of the masses of the elements in a compound, while constant,

More information

Experiment 7 Energy Accompanying Reactions. Objectives

Experiment 7 Energy Accompanying Reactions. Objectives Experiment 7 Energy Accompanying Reactions Objectives 1. To observe the techniques involved to remove water from a hydrated salt, copper (II) sulphate pentahydrate, CuSO 4 5H 2 O, quantitatively. 2. To

More information

Preparation of a Compound and Calculation of an Empirical Formula. By Justin Wright Portland Community College General Chemistry II 2/6/2013

Preparation of a Compound and Calculation of an Empirical Formula. By Justin Wright Portland Community College General Chemistry II 2/6/2013 Preparation of a Compound and Calculation of an Empirical Formula By Justin Wright Portland Community College General Chemistry II 2/6/2013 Abstract The purpose of this experiment was to determine the

More information

General Chemistry I (FC, 09-10) Lab #3: The Empirical Formula of a Compound. Introduction

General Chemistry I (FC, 09-10) Lab #3: The Empirical Formula of a Compound. Introduction General Chemistry I (FC, 09-10) Introduction A look at the mass relationships in chemistry reveals little order or sense. The ratio of the masses of the elements in a compound, while constant, does not

More information

EXPERIMENT 18: Formula of a Hydrate

EXPERIMENT 18: Formula of a Hydrate EXPERIMENT 18: Formula of a Hydrate Materials: Ring stand Ring crucible tongs Large evaporating dish Hot plate Balance Stirring rod Small dropper for water CuSO 4 5H 2 O Unknowns: MgSO 4 XH 2 O, FeSO 4

More information

Physical and Chemical Properties

Physical and Chemical Properties Physical and Chemical Properties Introduction Matter can be classified in different ways using physical and chemical properties. Physical properties include color, odor, density, hardness, structure, solubility,

More information

Unit 6 The Mole Concept

Unit 6 The Mole Concept Chemistry Form 3 Page 62 Ms. R. Buttigieg Unit 6 The Mole Concept See Chemistry for You Chapter 28 pg. 352-363 See GCSE Chemistry Chapter 5 pg. 70-79 6.1 Relative atomic mass. The relative atomic mass

More information

Upon completion of this lab, the student will be able to:

Upon completion of this lab, the student will be able to: 1 EXPERIMENT A3: HYDRATE Learning Outcomes Upon completion of this lab, the student will be able to: 1) Describe the differences between an anhydrous and hydrate compound. 2) Calculate the number of moles

More information

Determination of the Empirical Formula of Silver Oxide

Determination of the Empirical Formula of Silver Oxide P.O. Box 219 Batavia, Illinois 60510 1-800-452-1261 flinn@flinnsci.com Visit our website at: www.flinnsci.com Determination of the Empirical Formula of Silver Oxide AP Chemistry Laboratory # 1 Catalog

More information

Figure 1: Experimental Set-up with Leveling Bulb

Figure 1: Experimental Set-up with Leveling Bulb Gas Laws Equipment Set-up and Leveling bulb discussion: A buret will be used to collect our gas product, so we can measure the volume of gas produced accurately. A leveling bulb (a plastic bottle with

More information

Austin Peay State University Department of Chemistry CHEM 1111. Empirical Formula of a Compound

Austin Peay State University Department of Chemistry CHEM 1111. Empirical Formula of a Compound Cautions Magnesium ribbon is flammable. Nitric acid (HNO 3 ) is toxic, corrosive and contact with eyes or skin may cause severe burns. Ammonia gas (NH 3 ) is toxic and harmful. Hot ceramic crucibles and

More information

Laboratory Exercise: The Chemical Formula of a Hydrate

Laboratory Exercise: The Chemical Formula of a Hydrate CHEM 109 Introduction to Chemistry Revision 1.2 Laboratory Exercise: The Chemical Formula of a Hydrate In this laboratory exercise we will determine the relative amount of Water in a Hydrated compound.

More information

How Can the Percent Composition of a Salt, Sand and Iron Mixture be Determined?

How Can the Percent Composition of a Salt, Sand and Iron Mixture be Determined? Lab 2 Name How Can the Percent Composition of a Salt, Sand and Iron Mixture be Determined? Pre-Lab Assignment This written pre-lab is worth 15% (3 points) of your lab report grade and must be turned in

More information

CHM 130 Analysis of Copper Ore for Cu Content

CHM 130 Analysis of Copper Ore for Cu Content CHM 130 Analysis of Copper Ore for Cu Content Introduction: Copper, in various forms, has been mined from the Earth ever since mankind started using metal tools. Early Egyptian civilizations used bronze,

More information

Oxidation States of Copper Two forms of copper oxide are found in nature, copper(i) oxide and copper(ii) oxide.

Oxidation States of Copper Two forms of copper oxide are found in nature, copper(i) oxide and copper(ii) oxide. The Empirical Formula of a Copper Oxide Reading assignment: Chang, Chemistry 10 th edition, pp. 55-58. Goals The reaction of hydrogen gas with a copper oxide compound will be studied quantitatively. By

More information

MOLES, MOLECULES, FORMULAS. Part I: What Is a Mole And Why Are Chemists Interested in It?

MOLES, MOLECULES, FORMULAS. Part I: What Is a Mole And Why Are Chemists Interested in It? NAME PARTNERS SECTION DATE_ MOLES, MOLECULES, FORMULAS This activity is designed to introduce a convenient unit used by chemists and to illustrate uses of the unit. Part I: What Is a Mole And Why Are Chemists

More information

Experiment 10B DETERMINING THE MOLAR MASS OF A GAS

Experiment 10B DETERMINING THE MOLAR MASS OF A GAS Experiment 10B DETERMINING THE MOLAR MASS OF A GAS FV 3-31-16 MATERIALS: Dry 250 ml Erlenmeyer flask, piece of foil (~3 x 3 ), 800 ml beaker, 500 ml graduated cylinder, iron ring, ring stand, wire gauze,

More information

CHEMICAL REACTIONS OF COPPER AND PERCENT YIELD KEY

CHEMICAL REACTIONS OF COPPER AND PERCENT YIELD KEY CHEMICAL REACTIONS OF COPPER AND PERCENT YIELD Objective To gain familiarity with basic laboratory procedures, some chemistry of a typical transition element, and the concept of percent yield. Apparatus

More information

Mixtures and Pure Substances

Mixtures and Pure Substances Unit 2 Mixtures and Pure Substances Matter can be classified into two groups: mixtures and pure substances. Mixtures are the most common form of matter and consist of mixtures of pure substances. They

More information

Chemistry Types of Chemical Reactions

Chemistry Types of Chemical Reactions Chemistry Types of Chemical Reactions In this lab, you will be given an opportunity to differentiate between various reaction types, as well as practicing writing balanced equations for those reactions.

More information

Return to Lab Menu. Stoichiometry Exploring the Reaction between Baking Soda and Vinegar

Return to Lab Menu. Stoichiometry Exploring the Reaction between Baking Soda and Vinegar Return to Lab Menu Stoichiometry Exploring the Reaction between Baking Soda and Vinegar Objectives -to observe and measure mass loss in a gas forming reaction -to calculate CO 2 loss and correlate to a

More information

DETERMINATION OF THE PERCENT COMPOSITION OF A MIXTURE

DETERMINATION OF THE PERCENT COMPOSITION OF A MIXTURE Chemistry 111 Lab: Percent Composition Page D-3 DETERMINATION OF THE PERCENT COMPOSITION OF A MIXTURE In this experiment you are to determine the composition of a mixture containing unknown proportions

More information

Sugar or Salt? Ionic and Covalent Bonds

Sugar or Salt? Ionic and Covalent Bonds Lab 11 Sugar or Salt? Ionic and Covalent Bonds TN Standard 2.1: The student will investigate chemical bonding. Have you ever accidentally used salt instead of sugar? D rinking tea that has been sweetened

More information

Recovery of Elemental Copper from Copper (II) Nitrate

Recovery of Elemental Copper from Copper (II) Nitrate Recovery of Elemental Copper from Copper (II) Nitrate Objectives: Challenge: Students should be able to - recognize evidence(s) of a chemical change - convert word equations into formula equations - perform

More information

The Mole Concept. The Mole. Masses of molecules

The Mole Concept. The Mole. Masses of molecules The Mole Concept Ron Robertson r2 c:\files\courses\1110-20\2010 final slides for web\mole concept.docx The Mole The mole is a unit of measurement equal to 6.022 x 10 23 things (to 4 sf) just like there

More information

This acid is strong. Be careful.

This acid is strong. Be careful. Copper Conversions Lab Name Introduction In this multi-day lab you will start with a sample of copper metal and run several successive reactions which produce different copper compounds. The last reaction

More information

Chemical Changes. Measuring a Chemical Reaction. Name(s)

Chemical Changes. Measuring a Chemical Reaction. Name(s) Chemical Changes Name(s) In the particle model of matter, individual atoms can be bound tightly to other atoms to form molecules. For example, water molecules are made up of two hydrogen atoms bound to

More information

Chemistry 151 Last updated Dec Lab 6: Percent Composition and Empirical formulas

Chemistry 151 Last updated Dec Lab 6: Percent Composition and Empirical formulas Chemistry 151 Last updated Dec. 2012 Lab 6: Percent Composition and Empirical formulas Introduction In this lab, you will experimentally determine the percent composition of a copper chloride, which you

More information

What is the Percent Copper in a Compound?

What is the Percent Copper in a Compound? Lab 9 Name What is the Percent Copper in a Compound? Pre-Lab Assignment Complete this pre-lab on this sheet. This written pre-lab is worth 15% (3 points) of your lab report grade and must be initialed

More information

PHYSICAL AND CHEMICAL CHANGE EXPERIMENT 1

PHYSICAL AND CHEMICAL CHANGE EXPERIMENT 1 PURPOSE To investigate the criteria used to distinguish between physical and chemical changes in matter. 1 DEFINITIONS Chemical property, physical property, chemical change, physical change, conservation

More information

Determination of Aspirin using Back Titration

Determination of Aspirin using Back Titration Determination of Aspirin using Back Titration This experiment is designed to illustrate techniques used in a typical indirect or back titration. You will use the NaH you standardized last week to back

More information

AN EXPERIMENT IN ALCHEMY: COPPER TO SILVER TO GOLD 2005, 2000, 1996, 1979 by David A. Katz. All rights reserved

AN EXPERIMENT IN ALCHEMY: COPPER TO SILVER TO GOLD 2005, 2000, 1996, 1979 by David A. Katz. All rights reserved AN EXPERIMENT IN ALCHEMY: COPPER TO SILVER TO GOLD 2005, 2000, 1996, 1979 by David A. Katz. All rights reserved INTRODUCTION One of the goals of the ancient alchemists was to convert base metals into gold.

More information

EXPERIMENT 12: Empirical Formula of a Compound

EXPERIMENT 12: Empirical Formula of a Compound EXPERIMENT 12: Empirical Formula of a Compound INTRODUCTION Chemical formulas indicate the composition of compounds. A formula that gives only the simplest ratio of the relative number of atoms in a compound

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

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

Lecture Notes Chemistry E-1. Chapter 3

Lecture Notes Chemistry E-1. Chapter 3 Lecture Notes Chemistry E-1 Chapter 3 http://inserbia.info/news/wp-content/uploads/2013/05/tamiflu.jpg http://nutsforhealthcare.files.wordpress.com/2013/01/tamiflu-moa.jpg The Mole A mole is a certain

More information

Determining the Percent Composition of a Copper Chloride Hydrate

Determining the Percent Composition of a Copper Chloride Hydrate Determining the Percent Composition of a Copper Chloride Hydrate Overview: The mass percents of Cu, Cl and H 2 O in a compound are determined by separating and massing the three components. The resulting

More information

AN EXPERIMENT IN ALCHEMY: COPPER TO SILVER TO GOLD 2005, 2000, 1996 by David A. Katz. All rights reserved

AN EXPERIMENT IN ALCHEMY: COPPER TO SILVER TO GOLD 2005, 2000, 1996 by David A. Katz. All rights reserved AN EXPERIMENT IN ALCHEMY: COPPER TO SILVER TO GOLD 2005, 2000, 1996 by David A. Katz. All rights reserved INTRODUCTION One of the goals of the ancient alchemists was to convert base metals into gold. Although

More information

Determination of Aspirin using Back Titration

Determination of Aspirin using Back Titration Determination of Aspirin using Back Titration This experiment is designed to illustrate techniques used in a typical indirect or back titration. You will use the NaH you standardized last week to back

More information

Category III Physical science examples

Category III Physical science examples Category III Physical science examples Providing variety of phenomena Chemistry That Applies A sufficient number and variety of phenomena are used to support each of the key ideas. For the idea that mass

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

Name: Unit 2- Elements, Compounds and Mixtures and Physical/Chemical Properties and Changes. Elements, Compounds and Mixtures

Name: Unit 2- Elements, Compounds and Mixtures and Physical/Chemical Properties and Changes. Elements, Compounds and Mixtures Name: Unit 2- Elements, Compounds and Mixtures and Physical/Chemical Properties and Changes Day Page # Description IC/HW All 2 Warm-up IC 1 3 5 Matter Notes IC 1 6 Nuts & Bolts IC 1 7 Elements, Compounds

More information

Category 5 points 4 points 3 points 2 points 1 point 0 points Participation Participated fully. Mostly on-task. Safety reminders needed.

Category 5 points 4 points 3 points 2 points 1 point 0 points Participation Participated fully. Mostly on-task. Safety reminders needed. Lab Report Rubric Category 5 points 4 points 3 points 2 points 1 point 0 points Participation Participated fully Mostly on-task Minimal and Safety participation Prelab /10 Observations Data Units & Significant

More information

Calcium Carbonate Content of Limestone

Calcium Carbonate Content of Limestone EXPERIMENT Calcium Carbonate Content of Limestone 01 Prepared by Paul C. Smithson, Berea College OBJECTIVE Using chips of limestone rocks, students prepare a powdered sample of limestone, react it with

More information

The Synthesis of trans-dichlorobis(ethylenediamine)cobalt(iii) Chloride

The Synthesis of trans-dichlorobis(ethylenediamine)cobalt(iii) Chloride CHEM 122L General Chemistry Laboratory Revision 2.0 The Synthesis of trans-dichlorobis(ethylenediamine)cobalt(iii) Chloride To learn about Coordination Compounds and Complex Ions. To learn about Isomerism.

More information

Laboratory Exercise: Smelting of Lead

Laboratory Exercise: Smelting of Lead CHEM 109 Introduction to Chemistry Revision 1.0 Laboratory Exercise: Smelting of Lead In this laboratory exercise we will carry out a pyrometallurgical conversion of Lead Oxide into elemental Lead. This

More information

Unit 4 Lesson 1 Chemical Reactions. Copyright Houghton Mifflin Harcourt Publishing Company

Unit 4 Lesson 1 Chemical Reactions. Copyright Houghton Mifflin Harcourt Publishing Company Change It Up! What are the signs of a chemical reaction? A chemical reaction is the process in which atoms are rearranged to produce new substances. During a chemical reaction, the bonds that hold atoms

More information

Title: Training Lab 1 Chemistry 11100, Fall Use of a balance a balance is used to measure the mass of solids in the chemistry lab.

Title: Training Lab 1 Chemistry 11100, Fall Use of a balance a balance is used to measure the mass of solids in the chemistry lab. Title: Training Lab 1 Chemistry 11100, Fall 2012 Introduction The purpose of this lab is to introduce you to a series of techniques that you will use in chemistry lab. For this lab, you will be using the

More information

Determination of a Chemical Formula

Determination of a Chemical Formula 1 Determination of a Chemical Formula Introduction Molar Ratios Elements combine in fixed ratios to form compounds. For example, consider the compound TiCl 4 (titanium chloride). Each molecule of TiCl

More information

Experiment 8: Chemical Moles: Converting Baking Soda to Table Salt

Experiment 8: Chemical Moles: Converting Baking Soda to Table Salt Experiment 8: Chemical Moles: Converting Baking Soda to Table Salt What is the purpose of this lab? We want to develop a model that shows in a simple way the relationship between the amounts of reactants

More information

Reaction of Magnesium with Hydrochloric Acid (Gas Laws) Chemicals Needed:

Reaction of Magnesium with Hydrochloric Acid (Gas Laws) Chemicals Needed: Reaction of Magnesium with Hydrochloric Acid (Gas Laws) Your Name: Date: Partner(s) Names: Objectives: React magnesium metal with hydrochloric acid, collecting the hydrogen over water. Calculate the grams

More information

Determining Equivalent Weight by Copper Electrolysis

Determining Equivalent Weight by Copper Electrolysis Purpose The purpose of this experiment is to determine the equivalent mass of copper based on change in the mass of a copper electrode and the volume of hydrogen gas generated during an electrolysis reaction.

More information

COMMON LABORATORY APPARATUS

COMMON LABORATORY APPARATUS COMMON LABORATORY APPARATUS Beakers are useful as a reaction container or to hold liquid or solid samples. They are also used to catch liquids from titrations and filtrates from filtering operations. Bunsen

More information

Chapter 6, Lesson 3: Forming a Precipitate

Chapter 6, Lesson 3: Forming a Precipitate Chapter 6, Lesson 3: Forming a Precipitate Key Concepts The ions or molecules in two solutions can react to form a solid. A solid formed from two solutions is called a precipitate. Summary Students will

More information

Percent Composition, Empirical and Molecular Formulas

Percent Composition, Empirical and Molecular Formulas Percent Composition, Empirical and Molecular Formulas Chemists create new compounds for industry, pharmaceutical, and home use Analytical chemist analyzes new compound to provide proof of composition and

More information

General Chemistry Lab Experiment 4. Limiting Reactant

General Chemistry Lab Experiment 4. Limiting Reactant General Chemistry Lab Experiment 4 Limiting Reactant INTRODUCTION Two factors affect the yield of products in a chemical reaction: (1) the amounts of starting materials (reactants) and (2) the percent

More information

Chemical Reactions. Chemistry 100. Bettelheim, Brown, Campbell & Farrell. Introduction to General, Organic and Biochemistry Chapter 4

Chemical Reactions. Chemistry 100. Bettelheim, Brown, Campbell & Farrell. Introduction to General, Organic and Biochemistry Chapter 4 Chemistry 100 Bettelheim, Brown, Campbell & Farrell Ninth Edition Introduction to General, Organic and Biochemistry Chapter 4 Chemical Reactions Chemical Reactions In a chemical reaction, one set of chemical

More information

IDENTIFYING CARBOHYDRATES

IDENTIFYING CARBOHYDRATES (adapted from Blackburn et al., Laboratory Manual to Accompany World of Chemistry, 2 nd ed., (1996) Saunders College Publishing: Fort Worth) Purpose: To become familiar with some of the characteristic

More information

Chemical Equations & Stoichiometry

Chemical Equations & Stoichiometry Chemical Equations & Stoichiometry Chapter Goals Balance equations for simple chemical reactions. Perform stoichiometry calculations using balanced chemical equations. Understand the meaning of the term

More information

CH3 Stoichiometry. The violent chemical reaction of bromine and phosphorus. P.76

CH3 Stoichiometry. The violent chemical reaction of bromine and phosphorus. P.76 CH3 Stoichiometry The violent chemical reaction of bromine and phosphorus. P.76 Contents 3.1 Counting by Weighing 3.2 Atomic Masses 3.3 The Mole 3.4 Molar Mass 3.5 Percent Composition of Compounds 3.6

More information

Percent Composition. Percent Composition the percentage by mass of each element in a compound. Percent = Part Whole x 100%

Percent Composition. Percent Composition the percentage by mass of each element in a compound. Percent = Part Whole x 100% Percent Composition Percent Composition the percentage by mass of each element in a compound Percent = Part Whole x 100% Percent composition of a compound or = molecule Mass of element in 1 mol x 100%

More information

Types of Reactions: The Copper cycle

Types of Reactions: The Copper cycle Green Chemistry Module Level: High School Regents Types of Reactions: The Copper cycle Laboratory Experiment Created By: Dr. Martin Walker, State University of New York at Potsdam Module Contributors:

More information

Experiment 37. Stoichiometry. Introduction. Materials (for each lab team of 2 students)

Experiment 37. Stoichiometry. Introduction. Materials (for each lab team of 2 students) Eperiment 37 Stoichiometry Introduction Intent Students will determine the stoichiometry of a reaction between iron filings and copper(ii) sulfate. The students will determine the equation for the reaction

More information

Laboratory 2. Separation of the Components of a Mixture. Objectives. Introduction

Laboratory 2. Separation of the Components of a Mixture. Objectives. Introduction Laboratory 2 Separation of the Components of a Mixture Objectives Use extraction methods to separate the components of a mixture and determine the mass percent of each component of the mixture. Learn the

More information

Chapter Three: STOICHIOMETRY

Chapter Three: STOICHIOMETRY p70 Chapter Three: STOICHIOMETRY Contents p76 Stoichiometry - The study of quantities of materials consumed and produced in chemical reactions. p70 3-1 Counting by Weighing 3-2 Atomic Masses p78 Mass Mass

More information

Determination of Molecular Mass by Freezing Point Depression

Determination of Molecular Mass by Freezing Point Depression Determination of Molecular Mass by Freezing Point Depression Objectives: To determine the molecular mass of an unknown solid using the colligative property of freezing point depression. Background: When

More information

Endothermic and exothermic reactions. Performing different measurements to examine which reactions release or consume heat.

Endothermic and exothermic reactions. Performing different measurements to examine which reactions release or consume heat. Objective The purpose of this activity is to recognize chemical reactions as endothermic and exothermic. Students will then create a hypothesis and proceed to test it using the Labidisc external temperature

More information

Physical and Chemical Properties and Changes

Physical and Chemical Properties and Changes Physical and Chemical Properties and Changes An understanding of material things requires an understanding of the physical and chemical characteristics of matter. A few planned experiments can help you

More information

Experiment 12- Classification of Matter Experiment

Experiment 12- Classification of Matter Experiment Experiment 12- Classification of Matter Experiment Matter can be classified into two groups: mixtures and pure substances. Mixtures are the most common form of matter and consist of mixtures of pure substances.

More information

Combusting Candles. Category: Chemistry Type: Class Experiment (60 min) Materials List: Be careful! This activity involves working with open flames.

Combusting Candles. Category: Chemistry Type: Class Experiment (60 min) Materials List: Be careful! This activity involves working with open flames. Combusting Candles Category: Chemistry Type: Class Experiment (60 min) Materials List: 2 Tealight candles 1 Nail 1 Glass Jar with a flat top, e.g jam jar 1 Lighter or matches Video: (youtubelink) Be careful!

More information

PREPARATION FOR CHEMISTRY LAB: COMBUSTION

PREPARATION FOR CHEMISTRY LAB: COMBUSTION 1 1. What is a hydrocarbon? PREPARATION FOR CHEMISTRY LAB: COMBUSTION 2. Give an example of a combustion reaction? 3. What products form in the complete combustion of a hydrocarbon? Are these products

More information

PREPARATION FOR CHEMISTRY LAB: COMBUSTION

PREPARATION FOR CHEMISTRY LAB: COMBUSTION 1 Name: Lab Instructor: PREPARATION FOR CHEMISTRY LAB: COMBUSTION 1. What is a hydrocarbon? 2. What products form in the complete combustion of a hydrocarbon? 3. Combustion is an exothermic reaction. What

More information

In this experiment, we will use three properties to identify a liquid substance: solubility, density and boiling point..

In this experiment, we will use three properties to identify a liquid substance: solubility, density and boiling point.. Identification of a Substance by Physical Properties 2009 by David A. Katz. All rights reserved. Permission for academic use provided the original copyright is included Every substance has a unique set

More information

Chemical Reactions, Counting Atoms, and Balancing Chemical Equations.

Chemical Reactions, Counting Atoms, and Balancing Chemical Equations. Chemical Reactions, Counting Atoms, and Balancing Chemical Equations. A Chemical Reaction is A process where one or more elements or compounds are changed into one or more different substances A process

More information

Lab 1: Gravimetric Analysis of a Metal Carbonate

Lab 1: Gravimetric Analysis of a Metal Carbonate AP Chemistry Lab Date: Chemist: Lab Write Up Due Date: Lab 1: Gravimetric Analysis of a Metal Carbonate BACKGROUND How do chemists determine the identity of a compound? A large variety of analytical techniques

More information

experiment5 Understanding and applying the concept of limiting reagents. Learning how to perform a vacuum filtration.

experiment5 Understanding and applying the concept of limiting reagents. Learning how to perform a vacuum filtration. 81 experiment5 LECTURE AND LAB SKILLS EMPHASIZED Synthesizing an organic substance. Understanding and applying the concept of limiting reagents. Determining percent yield. Learning how to perform a vacuum

More information

1. 4 Which particle has two neutrons? 1.

1. 4 Which particle has two neutrons? 1. 1. 4 Which particle has two neutrons? 1. 2. 3. 4. 2. 1 Which electron configuration represents an atom of magnesium in an excited state? 1. 2 7 3 3. 2 8 2 2. 2 7 6 4. 2 8 5 3. 2 Which conclusion was drawn

More information