CHM101 Lab Acids and Bases Grading Rubric
|
|
- Irma Lambert
- 7 years ago
- Views:
Transcription
1 Name Team Name CHM101 Lab Acids and Bases Grading Rubric To participate in this lab you must have splash-proof goggles, proper shoes and attire. Criteria Points possible Points earned Lab Performance Printed lab handout and rubric was brought to lab 3 Safety and proper waste disposal procedures observed 2 Followed procedure correctly without depending too much on instructor or lab partner 3 Work space and glassware was cleaned up 1 Lab Report All observations accurately recorded 5 Question 1 1 Question 2 1 Question 3 1 Question 4 1 Question 5 2 Total 20 Subject to additional penalties at the discretion of the instructor.
2 Acids and Bases Goals: To determine the ph of common substances and observe buffer behavior. Background Acids and bases are very common in chemistry and biology. Understanding acids and bases is key to understanding many reactions in chemistry and biochemistry. The work acid comes from the Latin acidus meaning sour from acēre to be sharp. Acid solutions have a ph less than 7, turn blue litmus paper red, and taste sour. The name base was coined in the sense that bases react with acids and give them a solid form (turn them into salts). Bases have ph greater than 7, turn red litmus paper blue and tend to taste bitter. Acids and bases can be defined in different ways. The Arrhenius definition classified acids as substances which produce hydrogen ions (H + ) in water solutions (in water, H + really exists as hydronium (H 3O + ), but chemists often write just H + anyway). We can recognize them by the H in front of an anion with (aq). For example: HCl (aq) is an Arrhenius acid. Arrhenius bases are substances that dissociate into cations and hydroxide (OH - ) ions. For example: NaOH (aq) is an Arrhenius base. The Brønsted-Lowry definition expands the type of compounds that are considered acids and bases. A Brønsted-Lowry acid is defined as a proton (H + ) donor. By this definition, any compound that can lose H + can be considered an acid. Examples include all of the Arrhenius acids as well as compounds that we may not think of as acids like water and alcohols. A Brønsted Lowry base is defined as a substance that can accept H +. OH compounds will accept H + to make H 2O, but many other compounds will accept H + as well, such as ammonia (NH 3) or any compound with a lone pair. The Autoionization of Water and ph Water exists in equilibrium with hydronium and hydroxide (the autoionization of water.) H 2O(l) + H 2O(l) H 3O + (aq) + OH (aq) K w = [H 3O + ][OH ] The equilibrium constant for this reaction, K w, is equal to the hydronium time hydroxide concentration. At 25 o C, the value of K w is 1.0 x In pure water at 25 ⁰C, [H 3O + ] = 1.0 x 10 7 M and [OH ] = 1.0 x 10 7 M. The K w formula works for non-neutral solutions also. If the [H 3O + ] > [OH ], the solution is acidic and if [OH ] > [H 3O + ] then the solution is basic. ph is a way to express the acidity or basicity of a solution without having to write out concentrations with exponents.. ph = - log[h 3O + ] In neutral water ph = -log [1.0 x 10 7 M] = 7. Acidic solutions have ph less than 7. Basic solutions have ph greater than 7.
3 Here are some example values for [H + ] and ph, and next to them, what [OH ] and poh will be in the same solution. [H 3O + ] (molarity) ph [OH ] (molarity) poh 1 x 10 1 = 10 M -1 1 x M 15 1 x 10 0 = x x 10 1 = x x 10 2 = x x 10 3 = x x 10 4 = x x 10 5 = x x 10 6 = x x 10 7 = x x 10 8 = x x 10 9 = x x = x x = x x = x x = x x = x x = x There are many ways to measure ph. One such way is to use an indicator, which is a compound that changes color as the ph changes. Red litmus paper turns blue in the presence of a base, for example. A universal indicator contains several individual indicators mixed together the combined colors that can be used to estimate the ph in the range In this lab, we will use universal indicator solution, ph paper, or a red cabbage solution to estimate ph. Indicators are usually accurate to within one ph unit. To get more accurate measurements of ph, we will use a ph meter. The ph meter works by carefully measuring the voltage difference between your test solution, and another solution inside the probe with ph = 7. More ions in your solution creates a higher voltage difference. The probe uses a special glass barrier that only responds to H +, so that it will measure H + alone, without other ions interfering. This way, the ph can be measured to a few decimal places, especially with a high-quality ph meter. Buffers A buffer solution is a solution that resists a change in its ph upon the addition of small quantities of either a strong acid or a strong base. Buffers are usually made by mixing a weak acid and its conjugate base, or a weak base and its conjugate acid. For example, a solution containing NH 4Cl with NH 3 will be a buffer solution. In this lab we will make a buffer using HC 2H 3O 2 (aq) and NaC 2H 3O 2 (aq). Buffers work by neutralizing the added strong acid or base. When a strong acid is added (H 3O + ), it reacts with the weak base (C 2H 3O 2_ ) creating weak acid (HC 2H 3O 2) and water. Since the strong acid has reacted, the ph stays relatively stable. C 2H 3O 2 _ (aq) + H 3O + (aq) HC 2H 3O 2 (aq) + H 2O When a strong base (OH ) is added to a buffer it will react with the weak acid (HC 2H 3O 2) and produce a weak base (C 2H 3O 2_ ) and water. Since the strong base has reacted, the ph stays relatively stable. HC 2H 3O 2 (aq) + OH (aq) C 2H 3O 2 _ (aq) + H 2O
4 Laboratory Activity Materials: premade universal indicator solutions, ph 1-14 various household substances stirring rod universal indicator solution ph paper ph meter 0.10 M HCl 0.10 M NaOH Buffer solution (0.10 M sodium acetate in 0.10M acetic acid) Procedure A. Determination of ph of Household Substances 1. Your instructor will prepare a series of test tubes containing solutions of ph 1-13 treated with universal indicator. Record the color of each tube. Do not open the tubes! 2. Obtain 10 household substances. If the substance is a liquid, place 1-2 ml in a test tube. If the substance is a solid, add one spatula tip to the test tube then add about 1 ml of water. If the solid is in chunks or pill form, grind with a mortar and pestle before adding to the test tube. 3. Determine the ph using ph paper. To use ph paper: Do not dip the paper itself in the solution the indicators will dissolve in the solution. Dip a clean, dry stirring rod in the test tube. Remove the rod and touch it to ph paper. Estimate the ph by comparing the color of the paper to the color chart on the package 4. Determine the ph using universal indicator solution. To use universal indicator solution: Add 2 drops of indictor to the test tube and shake to distribute. Estimate the ph by comparing to the prepared solutions in step 1. B. ph of Unbuffered and Buffered Solutions 1. Clean two 25 ml beakers and place 10.0 ml of deionized water in each. Use a graduated cylinder to measure the required volume of water. 2. It is difficult to determine the ph of deionized water, so assume that the ph = Measure 1 ml of 0.10 M HCl with a pipette and add to one beaker. Stir and measure the ph with a ph meter. To use a ph meter: Rinse the probe with deionized water. Completely submerge the glass sphere of the probe in the liquid. Rinse again with deionized water after each reading. 4. Measure 1 ml of 0.10 M NaOH with a pipette and add to the other beaker. Stir and measure the ph meter. 5. Clean two new 25 ml beakers and place 10.0 ml of buffer solution (0.10M HC 2H 3O 2, 0.10 M NaC 2H 3O 2) in each. 6. Measure the ph of the buffer solution before adding acid and base. 7. Measure 1 ml of 0.10 M HCl with a pipette and add to one beaker of buffer. Stir and measure the ph meter. 8. Measure 1 ml of 0.10 M NaOH with a pipette and add to the other beaker of buffer. Stir and measure the ph meter. Waste Disposal Pour all solutions down the sink. Be sure to rinse all solid from test tubes before putting back.
5 Acids and Bases: Data Sheet Name A. Determination of ph of Household Substances Prepared Universal Indicator Solutions: ph Color Observed ph Color Observed Substance ph with indicator paper ph with universal indicator acidic, basic or neutral? Q1. Which household substance was the most acidic? Which household substance was the most basic? Report Page 1 of 3
6 Acids and Bases: Post Lab Name B. ph of Unbuffered and Buffered Solutions Solution ph Deionized water 7 Deionized water + 1 ml 0.10 M HCl Deionized water + 1 ml 0.10 M NaOH Buffer (0.10M HC 2H 3O 2, 0.10 M NaC 2H 3O 2) Buffer + 1 ml 0.10 M HCl Buffer + 1 ml 0.10 M NaOH Q2. a) Describe the difference in behavior of pure water and buffer solution when strong acids and bases are added: b) Why do buffers behave differently? Q3. Based on your measured ph, calculate the hydronium concentration of the solution: Deionized water ml 0.10 M NaOH. (show work) Q4. Based on your measured ph, calculate the hydroxide concentration of the solution: Buffer ml 0.10 M HCl. (show work) Report Page 3 of 3
7 Acids and Bases: Post Lab Name Q5. Complete the following table: [H 3O + ] [OH - ] ph acidic, basic, or neutral? 1.66 x 10-5 M 6.88 x 10-2 M x M Report Page 3 of 3
Properties of Acids and Bases
Lab 22 Properties of Acids and Bases TN Standard 4.2: The student will investigate the characteristics of acids and bases. Have you ever brushed your teeth and then drank a glass of orange juice? What
More informationEXPERIMENT 4 Acid Strength
EXPERIMENT 4 Acid Strength Introduction Many common substances are either acids or bases. Some acids, like stomach acid are necessary for our health, while others, like sulfuric acid are dangerous and
More informationEXPERIMENT 20: Determination of ph of Common Substances
Materials: ph paper and color chart (ph range 3 to 12) or ph meter distilled water white vinegar household ammonia (or baking soda) spot plate test or 3 small test tubes stirring rod solutions / fruits
More informationQ1: What is the ph Scale? Q6: As acids become more acidic, their ph values
Q1: What is the ph Scale? Q6: As acids become more acidic, their ph values increase or decrease? Q2: The range of values of the ph scale is: Q7: As bases become more alkaline, their ph values increase
More informationCHM 130LL: ph, Buffers, and Indicators
CHM 130LL: ph, Buffers, and Indicators Many substances can be classified as acidic or basic. Acidic substances contain hydrogen ions, H +, while basic substances contain hydroxide ions, OH. The relative
More informationChem101: General Chemistry Lecture 9 Acids and Bases
: General Chemistry Lecture 9 Acids and Bases I. Introduction A. In chemistry, and particularly biochemistry, water is the most common solvent 1. In studying acids and bases we are going to see that water
More informationChemistry 52. Reacts with active metals to produce hydrogen gas. Have a slippery, soapy feeling. React with carbonates to produce CO 2
ACID AND BASE STRENGTH Experiment #2 PURPOSE: 1. To distinguish between acids, bases and neutral substances, by observing their effect on some common indicators. 2. To distinguish between strong and weak
More informationChapter 17. How are acids different from bases? Acid Physical properties. Base. Explaining the difference in properties of acids and bases
Chapter 17 Acids and Bases How are acids different from bases? Acid Physical properties Base Physical properties Tastes sour Tastes bitter Feels slippery or slimy Chemical properties Chemical properties
More informationph: Measurement and Uses
ph: Measurement and Uses One of the most important properties of aqueous solutions is the concentration of hydrogen ion. The concentration of H + (or H 3 O + ) affects the solubility of inorganic and organic
More informationExperiment 9: Acids and Bases Adapted from: Chemistry, Experimental Foundations, 4th Ed. Laboratory Manual, by Merrill, Parry & Bassow.
Chem 121 Lab Clark College Experiment 9: Acids and Bases Adapted from: Chemistry, Experimental Foundations, 4th Ed. Laboratory Manual, by Merrill, Parry & Bassow. Content Goals: Increase understanding
More informationChemistry 3202. Unit 2 Acids and Bases
Chemistry 3202 Unit 2 Acids and Bases Definitions of Acids and Bases An operational definition is one that is based on the observable properties, behaviours or uses of an entity. The earliest definitions
More informationChapter 14: Acids and Bases
Ch 14 Page 1 Chapter 14: Acids and Bases Properties of Acids Sour taste React with some metals Turns blue litmus paper red React with bases Some Common Acids HCl, hydrochloric acid H 2 SO 4, sulfuric acid
More informationAcids and Bases HW PSI Chemistry
Acids and Bases HW PSI Chemistry Name 1) According to the Arrhenius concept, an acid is a substance that. A) is capable of donating one or more H + B) causes an increase in the concentration of H + in
More informationAn acid is a substance that produces H + (H 3 O + ) Ions in aqueous solution. A base is a substance that produces OH - ions in aqueous solution.
Chapter 8 Acids and Bases Definitions Arrhenius definitions: An acid is a substance that produces H + (H 3 O + ) Ions in aqueous solution. A base is a substance that produces OH - ions in aqueous solution.
More informationTOPIC 11: Acids and Bases
TOPIC 11: Acids and Bases ELECTROLYTES are substances that when dissolves in water conduct electricity. They conduct electricity because they will break apart into Ex. NaCl(s)! Na + (aq) + Cl - (aq), and
More informationAcids and Bases. An Introduction. David A Katz Department of Chemistry Pima Community College, Tucson, AZ, USA
Acids and Bases An Introduction David A Katz Department of Chemistry Pima Community College, Tucson, AZ, USA Properties of Acids 1. Sour taste (examples: vinegar, citric acid, lemon juice) 2. Turns litmus
More informationHealth Science Chemistry I CHEM-1180 Experiment No. 12 Acids, Bases, ph, Hydrolysis and Buffers (Revised 05/27/2015)
Health Science Chemistry I CHEM-1180 Experiment No. 12 Acids, Bases, ph, Hydrolysis and Buffers (Revised 05/27/2015) Introduction Hydrogen Ion Concentration The acidity of aqueous solutions and its measurement
More informationNeutralization Reactions. Evaluation copy
Neutralization Reactions Computer 6 If an acid is added to a base, a chemical reaction called neutralization occurs. An example is the reaction between nitric acid, HNO 3, and the base potassium hydroxide,
More informationAcids and Bases: A Brief Review
Acids and : A Brief Review Acids: taste sour and cause dyes to change color. : taste bitter and feel soapy. Arrhenius: acids increase [H ] bases increase [OH ] in solution. Arrhenius: acid base salt water.
More informationChapter 14 - Acids and Bases
Chapter 14 - Acids and Bases 14.1 The Nature of Acids and Bases A. Arrhenius Model 1. Acids produce hydrogen ions in aqueous solutions 2. Bases produce hydroxide ions in aqueous solutions B. Bronsted-Lowry
More informationCHAPTER 16: ACIDS AND BASES
CHAPTER 16: ACIDS AND BASES Active Learning: 4, 6, 14; End-of-Chapter Problems: 2-25, 27-58, 66-68, 70, 75-77, 83, 90-91, 93-104 Chapter 15 End-of-Chapter Problems: 69-74, 125, 129, 133 16.1 ACIDS AND
More informationUNIT (6) ACIDS AND BASES
UNIT (6) ACIDS AND BASES 6.1 Arrhenius Definition of Acids and Bases Definitions for acids and bases were proposed by the Swedish chemist Savante Arrhenius in 1884. Acids were defined as compounds that
More informationWrite the acid-base equilibria connecting all components in the aqueous solution. Now list all of the species present.
Chapter 16 Acids and Bases Concept Check 16.1 Chemists in the seventeenth century discovered that the substance that gives red ants their irritating bite is an acid with the formula HCHO 2. They called
More informationMULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.
CHE 1400 - Spring 2015 - Chapter 7 Homework 7 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1)According to Arrhenius, an acid and a base will react
More informationQ.1 Classify the following according to Lewis theory and Brønsted-Lowry theory.
Acid-base A4 1 Acid-base theories ACIDS & BASES - IONIC EQUILIBRIA 1. LEWIS acid electron pair acceptor H, AlCl 3 base electron pair donor NH 3, H 2 O, C 2 H 5 OH, OH e.g. H 3 N: -> BF 3 > H 3 N BF 3 see
More informationAcid-Base (Proton-Transfer) Reactions
Acid-Base (Proton-Transfer) Reactions Chapter 17 An example of equilibrium: Acid base chemistry What are acids and bases? Every day descriptions Chemical description of acidic and basic solutions by Arrhenius
More informationExperiment 8 - Double Displacement Reactions
Experiment 8 - Double Displacement Reactions A double displacement reaction involves two ionic compounds that are dissolved in water. In a double displacement reaction, it appears as though the ions are
More informationNote: (H 3 O + = hydronium ion = H + = proton) Example: HS - + H 2 O H 3 O + + S 2-
AcidBase Chemistry Arrhenius acid: Substance that dissolves in water and provides H + ions Arrhenius base: Substance that dissolves in water and provides OH ions Examples: HCl H + and Cl Acid NaOH Na +
More informationph units constitute a scale which allows scientists to determine the acid or base content of a substance or solution. The ph 0
ACID-BASE TITRATION LAB PH 2.PALM INTRODUCTION Acids and bases represent a major class of chemical substances. We encounter them every day as we eat, clean our homes and ourselves, and perform many other
More informationAcids and Bases. Chapter 16
Acids and Bases Chapter 16 The Arrhenius Model An acid is any substance that produces hydrogen ions, H +, in an aqueous solution. Example: when hydrogen chloride gas is dissolved in water, the following
More informationElectrical Conductivity of Aqueous Solutions
Electrical Conductivity of Aqueous Solutions PRE-LAB ASSIGNMENT: Reading: Chapter 4.-4.3 in Brown, LeMay, Bursten & Murphy.. Using Table in this handout, determine which solution has a higher conductivity,.
More informationUnit Two: Acids and Bases
Section One: Theoretical Stuff Unit Two: Acids and Bases The concept of acids and bases has existed for centuries. We can discuss them two ways, operational definitions and theoretical definitions. 1.
More informationAcid Dissociation Constants and the Titration of a Weak Acid
Acid Dissociation Constants and the Titration of a Weak Acid One of the most important applications of equilibria is the chemistry of acids and bases. The Brønsted-Lowry acid-base theory defines an acid
More informationEXPERIMENT 10 Chemistry 110. Solutions Part 2 ACIDS, BASES, AND ELECTROLYTES
EXPERIMENT 10 Chemistry 110 Solutions Part 2 ACIDS, BASES, AND ELECTROLYTES PURPOSE: The purpose of this experiment is to determine the properties of solutions of acids, bases and electrolytes. Students
More informationThe Acid Test Grade Nine
Ohio Standards Connection: Physical Sciences Benchmark B Explain how atoms react with each other to form other substances and how molecules react with each other or other atoms to form even different substances.
More informationSyllabus OC18 Use litmus or a universal indicator to test a variety of solutions, and classify these as acidic, basic or neutral
Chemistry: 9. Acids and Bases Please remember to photocopy 4 pages onto one sheet by going A3 A4 and using back to back on the photocopier Syllabus OC18 Use litmus or a universal indicator to test a variety
More informationAcids, Bases, and ph
CHAPTER 9 1 SECTION Acids, Bases, and Salts Acids, Bases, and ph KEY IDEAS As you read this section, keep these questions in mind: What properties do acids have? What properties do bases have? How can
More informationThe Determination of Acid Content in Vinegar
The Determination of Acid Content in Vinegar Reading assignment: Chang, Chemistry 10 th edition, pages 153-156. Goals We will use a titration to determine the concentration of acetic acid in a sample of
More informationQ.1 Classify the following according to Lewis theory and Brønsted-Lowry theory.
Acid-base 2816 1 Acid-base theories ACIDS & BASES - IONIC EQUILIBRIA LEWIS acid electron pair acceptor H +, AlCl 3 base electron pair donor NH 3, H 2 O, C 2 H 5 OH, OH e.g. H 3 N: -> BF 3 > H 3 N + BF
More informationNeutralizing an Acid and a Base
Balancing Act Teacher Information Objectives In this activity, students neutralize a base with an acid. Students determine the point of neutralization of an acid mixed with a base while they: Recognize
More informationCHM1 Review for Exam 12
Topics Solutions 1. Arrhenius Acids and bases a. An acid increases the H + concentration in b. A base increases the OH - concentration in 2. Strong acids and bases completely dissociate 3. Weak acids and
More informationTopic 8 Acids and bases 6 hours
Topic 8 Acids and bases 6 hours Hydronium ion (H3O + ) = more stable form of hydrogen ion (H + ) H + + H2O H3O + 8.1 Theories of acids and bases 2 hours 1. Arrhenius H-X / M-OH ACID a substance that dissociates
More informationTo determine the equivalence points of two titrations from plots of ph versus ml of titrant added.
Titration Curves PURPOSE To determine the equivalence points of two titrations from plots of ph versus ml of titrant added. GOALS 1 To gain experience performing acid-base titrations with a ph meter. 2
More informationAuto-ionization of Water
2H 2 O H 3 O + + OH Hydronium ion hydroxide ion Q: But how often does this happen? This is the fundamental concept of all acid-base chemistry In pure water, how much of it is water and how much is ions?
More informationChapter 19: Acids and Bases Homework Packet (50 pts) Name: Score: / 50
Chapter 19: Acids and Bases Homework Packet (50 pts) Topic pg Section 19.1 1-3 Section 19.2 3-6 Section 19.3 6-7 Section 19.4 8 Naming Acids 9 Properties of Acids/Bases 10-11 Conjugate Acid/Base Pairs
More informationAcid Base Titrations
Acid Base Titrations Introduction A common question chemists have to answer is how much of something is present in a sample or a product. If the product contains an acid or base, this question is usually
More informationReturn to Lab Menu. Acids and Bases in Your House
Return to Lab Menu Acids and Bases in Your House OBJECTIVES Isolate a natural acid-base indicator. Determine the acid-base properties of common household solutions. INTRODUCTION Acids and bases are among
More informationChapter 16 Acid-Base Equilibria
Chapter 16 Acid-Base Equilibria Learning goals and key skills: Understand the nature of the hydrated proton, represented as either H + (aq) or H 3 O + (aq) Define and identify Arrhenuis acids and bases.
More informationEXPERIMENT INTRODUCTION TO INDICATORS AND ACID-BASE TITRATIONS
EXPERIMENT INTRODUCTION TO INDICATORS AND ACID-BASE TITRATIONS By Dale A. Hammond, PhD, Brigham Young University Hawaii LEARNING OBJECTIVES The objectives of this experiment are... an introduction to ph
More informationChapter 9 Lecture Notes: Acids, Bases and Equilibrium
Chapter 9 Lecture Notes: Acids, Bases and Equilibrium Educational Goals 1. Given a chemical equation, write the law of mass action. 2. Given the equilibrium constant (K eq ) for a reaction, predict whether
More information6) Which compound is manufactured in larger quantities in the U.S. than any other industrial chemical?
MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which statement concerning Arrhenius acid-base theory is not correct? A) Acid-base reactions must
More informationChem 1B Saddleback College Dr. White 1. Experiment 8 Titration Curve for a Monoprotic Acid
Chem 1B Saddleback College Dr. White 1 Experiment 8 Titration Curve for a Monoprotic Acid Objectives To learn the difference between titration curves involving a strong acid with a strong base and a weak
More informationAcids, Bases, and Indicators Colorful Chemistry
Cool Chemistry Show Activity 7 Acids, Bases, and Indicators Colorful Chemistry GOALS In this activity you will: Identify common household acids and bases. Identify characteristic properties of acids and
More informationIntroduction. ph = log [H + ]
Visualizing ph 2010, 1992 by David A. Katz. All rights reserved. Permission granted for classroom use. All reproductions must include original copyright. David A. Katz Chemist, Educator, Science Communicator,
More informationCHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS
CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS Purpose: It is important for chemists to be able to determine the composition of unknown chemicals. This can often be done by way of chemical tests.
More informationChapter 16: Acid-Base and Solubility Equilibria: Reactions in Soil and Water
Chapter 16: Acid-Base and Solubility Equilibria: Reactions in Soil and Water Problems: 16.2-16.86 16.1 ACIDS AND BASES: THE BRØNSTED-LOWRY MODEL PROPERTIES OF ACIDS & BASES Acids produce hydrogen ions,
More informationAcids and Bases. AND a widemouth container of the following solids:
Acids and Bases GOAL To introduce students to acids and bases. MATERIALS: 3 10oz clear plastic cups 1 4 oz. bottle white vinegar - labeled Acid 1 4 oz. bottle of water - labeled Water 1 4 oz. bottle of
More informationChemistry 119: Experiment 7. Potentiometric Titration of Ascorbic Acid in Vitamin C Tablets
Chemistry 119: Experiment 7 Potentiometric Titration of Ascorbic Acid in Vitamin C Tablets Vitamin C is another name for ascorbic acid (C 6 H 8 O 6, see below ), a weak acid that can be determined by titration
More informationDETERMINATION OF PHOSPHORIC ACID CONTENT IN SOFT DRINKS
DETERMINATION OF PHOSPHORIC ACID CONTENT IN SOFT DRINKS LAB PH 8 From Chemistry with Calculators, Vernier Software & Technology, 2000 INTRODUCTION Phosphoric acid is one of several weak acids that present
More informationTitrations. Acid-Base Indicators and Titration Curves. Shapes of Titration Curves. A titration curve is a graphical history of a titration
Acid-Base Indicators and Titration Curves Titrations In a titration a solution of accurately known concentration is added gradually added to another solution of unknown concentration until the chemical
More informationVolumetric Analysis. Lecture 5 Experiment 9 in Beran page 109 Prelab = Page 115
Volumetric Analysis Lecture 5 Experiment 9 in Beran page 109 Prelab = Page 115 Experimental Aims To prepare and standardize (determine concentration) a NaOH solution Using your standardized NaOH calculate
More informationChapter 17. The best buffer choice for ph 7 is NaH 2 PO 4 /Na 2 HPO 4. 19)
Chapter 17 2) a) HCl and CH 3 COOH are both acids. A buffer must have an acid/base conjugate pair. b) NaH 2 PO 4 and Na 2 HPO 4 are an acid/base conjugate pair. They will make an excellent buffer. c) H
More informationCHAPTERS 15 FAKE TEST QUESTIONS. 1. According to the Brønsted Lowry definition, which species can function both as an acid and as a base?
You might need to know the following K values: CHAPTERS 15 FAKE TEST QUESTIONS CH 3 COOH K a = 1.8 x 10 5 Benzoic Acid K a = 6.5 x 10 5 HNO 2 K a = 4.5 x 10 4 NH 3 K b = 1.8 x 10 5 HF K a = 7.2 x 10 4
More informationExperiment 17: Potentiometric Titration
1 Experiment 17: Potentiometric Titration Objective: In this experiment, you will use a ph meter to follow the course of acid-base titrations. From the resulting titration curves, you will determine the
More informationExperiment 16-Acids, Bases and ph
Definitions acid-an ionic compound that releases or reacts with water to form hydrogen ion (H + ) in aqueous solution. They taste sour and turn litmus red. Acids react with certain metals such as zinc,
More informationTo see how this data can be used, follow the titration of hydrofluoric acid against sodium hydroxide below. HF (aq) + NaOH (aq) H2O (l) + NaF (aq)
Weak Acid Titration v120413 You are encouraged to carefully read the following sections in Tro (2 nd ed.) to prepare for this experiment: Sec 4.8, pp 158-159 (Acid/Base Titrations), Sec 16.4, pp 729-43
More informationSuggested Problems: p. 625-627 #58, 59, 65, 69, 74, 80, 85, 86, 90, 92, 93, 98, 99
Chemistry I Accelerated Study Guideline - Chapter 19 Acids, Bases and Salts ------------------------------------------------------------------------------ By the end of this unit, the skills you should
More informationProperties of Acids and Bases
Properties of Acids and Bases (Adapted from Flinn Scientific Acid Base Test Kit I #AP4567) Introduction Battery acid, stomach acid, acid rain just a few acids in our everyday life! What does it mean when
More informationA PRIMER ON ph. A Presentation for ASTA Conference September 30-October 1, 2008
A PRIMER ON ph A Presentation for ASTA Conference September 30-October 1, 2008 Rebecca Richardson Martha Gothard Director Science Specialist Regional In-Service Education Center AMSTI University of Montevallo
More informationSince we will be dealing with aqueous acid and base solution, first we must examine the behavior of water.
Acids and Bases Know the definition of Arrhenius, Bronsted-Lowry, and Lewis acid and base. Autoionization of Water Since we will be dealing with aqueous acid and base solution, first we must examine the
More informationRecovery 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 informationAcid-Base Titrations Using ph Measurements
Acid-Base Titrations Using ph Measurements Introduction According to the Brønsted Lowry definition, an acid is a substance that donates a hydrogen ion and a base is a substance which will accept a hydrogen
More informationph Measurements of Common Substances
Chem 100 Section Experiment 10 Name Partner s Name Introduction ph Measurements of Common Substances The concentration of an acid or base is frequently expressed as ph. Historically, ph stands for the
More informationEXPERIMENT 10: TITRATION AND STANDARDIZATION
EXPERIMENT 10: TITRATION AND STANDARDIZATION PURPOSE To determine the molarity of a NaOH solution by titrating it with a standard HCl solution. To determine the molarity of acetic acid in vinegar using
More informationName period Unit 9: acid/base equilibrium
Name period Unit 9: acid/base equilibrium 1. What is the difference between the Arrhenius and the BronstedLowry definition of an acid? Arrhenious acids give H + in water BronstedLowry acids are proton
More informationSolubility Product Constants
Solubility Product Constants PURPOSE To measure the solubility product constant (K sp ) of copper (II) iodate, Cu(IO 3 ) 2. GOALS 1 To measure the molar solubility of a sparingly soluble salt in water.
More informationHousehold Acids and Bases
Household Acids and Bases GRADE LEVEL INDICATORS Experiment Demonstrate that the ph scale (0-14) is used to measure acidity and classify substances or solutions as acidic, basic, or neutral. 21 Develop
More informationLab #10 How much Acetic Acid (%) is in Vinegar?
Lab #10 How much Acetic Acid (%) is in Vinegar? SAMPLE CALCULATIONS NEED TO BE DONE BEFORE LAB MEETS!!!! Purpose: You will determine the amount of acetic acid in white vinegar (sold in grocery stores)
More informationProperties of Aqueous Solutions of Acids and Bases. CHAPTER 10 Acids, Bases and Salts. Properties of Aqueous Solutions of Acids and Bases
CAPTER Acids, Bases and Salts Properties of Aqueous Solutions of Acids and Bases Strong and Weak Acids Acids are substances that generate in aqueous solutions. Strong acids ionize 0% in water. That is,
More informationChemistry Unit Test Review
SNC 2DI Chemistry Unit Test Review Note: this review sheet only covers the second half of our chemistry unit. You should use our mid-unit test review sheet to recall concepts from the first half of the
More informationAscorbic 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! Introduction Vitamin C (also known as ascorbic acid, HC6H7O6) is a necessary ingredient
More informationLab 25. Acid-Base Titration and Neutralization Reactions: What Is the Concentration of Acetic Acid in Each Sample of Vinegar?
Lab 25. Acid-Base Titration and Neutralization Reactions: What Is the Concentration of Acetic Acid in Each Sample of Vinegar? Introduction Vinegar is basically a solution of acetic acid (CH3COOH). It is
More informationAcetic Acid Content of Vinegar: An Acid-Base Titration E10-1
Experiment 10 Acetic Acid Content of Vinegar: An Acid-Base Titration E10-1 E10-2 The task The goal of this experiment is to determine accurately the concentration of acetic acid in vinegar via volumetric
More informationACID-BASE REACTIONS/ THE PH CONCEPT.
Dr Mike Lyons School of Chemistry Trinity College Dublin. melyons@tcd.ie ACID-BASE REACTIONS/ THE PH CONCEPT. Chemistry Preliminary Course 2011 1 Lecture topics. 2 lectures dealing with some core chemistry
More informationWhat does pka tell you?
ph and pka What does pka tell you? pka tells you if a given molecule is going to either give a proton to water at a certain ph, or remove a proton A pka of 2 for substance X means that at a ph of 2, X
More informationQUESTION (2012:3) (a) (i) Complete the table below showing the conjugate acids and bases. CO 3 H 2 O OH HCN CN -
QUESTION (2012:3) (i) Complete the table below showing the conjugate acids and bases. Conjugate acid Conjugate base - HCO 3 2 CO 3 H 2 O OH HCN CN - (ii) HPO 4 2 (aq) Write equations for the reactions
More informationDetermining the Identity of an Unknown Weak Acid
Purpose The purpose of this experiment is to observe and measure a weak acid neutralization and determine the identity of an unknown acid by titration. Introduction The purpose of this exercise is to identify
More informationAcid Base Titration: ph Titration Curve
Acid Base Titration: ph Titration Curve OVERVIEW In this experiment, you will perform a ph-monitored titration of acetic acid and of an unknown acid. From the ph titration of the acetic acid, you will
More informationAcids & Bases Around the House Use a ph indicator to find acids and bases
Use a ph indicator to find acids and bases Description: Visitors predict whether various household solutions are acids or bases, and test their hypotheses using a universal ph indicator. Then, visitors
More informationAcids & Bases: Using Purple Cabbage as a ph indicator. Grade 9 Activity Plan
Acids & Bases: Using Purple Cabbage as a ph indicator Grade 9 Activity Plan 1 Acids, Bases & Purple Cabbage Objectives: 1. To demonstrate the basic physical and chemical properties of acids and bases.
More informationExperiment 7: Titration of an Antacid
1 Experiment 7: Titration of an Antacid Objective: In this experiment, you will standardize a solution of base using the analytical technique known as titration. Using this standardized solution, you will
More information3 The Preparation of Buffers at Desired ph
3 The Preparation of Buffers at Desired ph Objectives: To become familiar with operating a ph meter, and to learn how to use the Henderson-Hasselbalch equation to make buffer solutions at a desired ph
More informationDissolving of sodium hydroxide generates heat. Take care in handling the dilution container.
TITRATION: STANDARDIZATION OF A BASE AND ANALYSIS OF STOMACH ANTACID TABLETS 2009, 1996, 1973 by David A. Katz. All rights reserved. Reproduction permitted for education use provided original copyright
More informationLab #13: Qualitative Analysis of Cations and Anions
Lab #13: Qualitative Analysis of Cations and Anions Objectives: 1. To understand the rationale and the procedure behind the separation for various cations and anions. 2. To perform qualitative analysis
More informationEXPERIMENT # 3 ELECTROLYTES AND NON-ELECTROLYTES
EXPERIMENT # 3 ELECTROLYTES AND NON-ELECTROLYTES Purpose: 1. To investigate the phenomenon of solution conductance. 2. To distinguish between compounds that form conducting solutions and compounds that
More informationexperiment5 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 informationAcid Base Chemistry. Farmington Public Schools Grade Level: 10 Discipline:Chemistry
Acid Base Chemistry Farmington Public Schools Grade Level: 10 Discipline:Chemistry Author(s) Gary Crisanti Heather Rauf DRAFT: 06/30/06 Farmington Public Schools Table of Contents Unit Summary.3...page(s)
More informationEXPERIMENT 12 A SOLUBILITY PRODUCT CONSTANT
PURPOSE: 1. To determine experimentally the molar solubility of potassium acid tartrate in water and in a solution of potassium nitrate. 2. To examine the effect of a common ion on the solubility of slightly
More informationSketch the model representation of the first step in the dissociation of water. H 2. O (l) H + (aq) + OH- (aq) + H 2. OH - (aq) + H 3 O+ (aq)
Lesson Objectives Students will: Create a physical representation of the autoionization of water using the water kit. Describe and produce a physical representation of the dissociation of a strong acid
More informationGeneral Chemistry II Chapter 20
1 General Chemistry II Chapter 0 Ionic Equilibria: Principle There are many compounds that appear to be insoluble in aqueous solution (nonelectrolytes). That is, when we add a certain compound to water
More information