25.1 Acids, Bases, and ph

Save this PDF as:
 WORD  PNG  TXT  JPG

Size: px
Start display at page:

Download "25.1 Acids, Bases, and ph"

Transcription

1 In the Investigations, you measured several indicators of water quality, including the ph. You may remember that ph values range from 0 to 14. Low values (0 to 6) indicate that a solution is acidic whereas high values (8 to 14) indicate that a solution is basic. Your stomach secretes one of the stronger acids, hydrochloric acid (HCl). As acidic solutions of digested food leave your stomach, other organs in your digestive system secrete bicarbonate, a base. The added base neutralizes the strong, corrosive acid. As you can see, acids and bases play a significant role in how your body works. What exactly are acids and bases? What does ph mean? Why is ph important? The ph of water indicates its quality are defined by ph values Water quality is evaluated using ph values for many reasons. For example, if the ph of your tap water is too high, it might indicate that calcium or magnesium deposits are forming in and may clog your water pipes. On the other hand, if the ph is too low, the water may be corroding your pipes. The ph of water is important to life. The ph of natural bodies of water also has to be just right neither too high nor too low. For example, at a ph of 4 or 5, fish have trouble reproducing. At even lower ph values, they die. The ph of water is related to the action of a class of chemicals called acids and bases. A solution with a ph value that is less than 7 contains an acid, and a solution with ph values greater than 7 contains a base. You will learn how ph is determined later on in this section. What are acids and bases? Acidic solutions have more H+ ions, and basic solutions have more OH- ions An acid is a chemical that contributes hydrogen ions, H+, to a solution. A base is a chemical that contributes hydroxyl ions, OH-, to a solution. Therefore, solutions can be described as acidic or basic according to the concentrations of H+ and OH- ions in the solution. A solution with a high concentration of H+ ions and few OH- ions is strongly acidic. A strongly basic (or alkaline) solution has a high concentration of OH- ions and few H+ ions. Figure 25.1: play important roles in digestion. 429

2 HCl is an acid NaOH is a base Weak acids and bases Hydrochloric acid (HCl) is a very strong acid which can seriously irritate your nose if you smell it and your skin if it spills on you! When HCl dissolves in water (as indicated by the symbol aq ), it ionizes to become H+ ions and Cl- ions: An acid such as HCl ionizes almost completely when dissolved in water and therefore contributes many H+ ions to a solution. Because of this, HCl is a known as a strong acid. Sodium hydroxide (NaOH) is a base commonly used for rigorous housecleaning and for unclogging drains. As you can see from the chemical formula, NaOH will release OH- ions when it dissolves in water: Since NaOH ionizes almost completely when dissolved in water and contributes many OH- ions to a solution, it is known as a strong base. Many acids and bases do not ionize completely in water and are known as weak acids and bases. Vinegar, also known as acetic acid, is a weak acid because it contributes a few H+ ions to solution. Vinegar is sometimes used for cleaning but is not very irritating to the skin. Your nose may not like it, however! Hydronium Ions In an acid solution, separate hydrogen ions (H+) do not exist by themselves for very long. Each hydrogen ion is attracted to the oxygen end of a water molecule. The two combine to form a hydronium ion. In chemistry, it is common to refer to H 3 O+ ions as H+ ions. A weak acid or base ionizes incompletely when dissolved in water as shown by the double arrows in the chemical equation above. Household ammonia is an example of a weak base because it does not completely ionize in water. 430

3 ph and the ph scale ph is based on the concentration of H+ ions in solution ph 7 means equal H+ and OH- ions Low ph means high H+ concentration The ph scale is based on powers of 10 Acids have more H+ ions, bases have more OHions Just as centimeters describe length, ph describes the exact concentrations of H+ ions in a solution. Most instruments that measure ph use a ph scale that runs from 0 to 14. At ph 1, a solution is strongly acidic. At ph 14, a solution is strongly basic, or alkaline. A solution that has a ph of 7 has equal numbers of H+ and OH- ions and is called a neutral solution. Everyone is familiar with using a ruler to measure things. However, a ph scale is different from a ruler in that the more H+ ions there are in a solution, the lower the ph value. Conversely, fewer H+ ions in a solution means a higher ph value. A ph scale is based on powers of ten. A solution that is ph 1 has 10 times more hydrogen ions than a solution of ph 2. In turn, the ph 2 solution has 10 times more hydrogen ions than a solution of ph 3. Another way of looking at the scale is to see that as the ph numbers increase, the amount of H+ ions decreases by powers of 10. Figure 25.2 illustrates the ph scale. For example, a solution at ph 1 has 10 million times more hydrogen ions than a solution at ph 7, and a solution at ph 7 has 10 million times more hydrogen ions than a solution at ph 14! You now know that the amount of H+ in a solution at ph 6 is 10 times the amount in a solution at ph 7. But a solution at ph 7 is neutral. What is the amount of OHions in a neutral solution? What is the amount of OH- ions in a solution at ph 6? The answers to these questions are that the amount of OH- ions in a neutral solution is equal to the amount of H+ ions. If you go down the ph scale to 6, the amount of OH- ions decreases by a power of 10 whereas the amount of H+ increases by a power of 10. Remember: ph values below 7 means H+ ions outnumber OH- ions, and ph values higher than 7 means OH- ions outnumber H+ ions. Since each ph is an increase or decrease by tenfold, there is a big difference in ion concentration between each ph value. Figure 25.2: The ph scale is based on the concentration of hydrogen ions in solution. 431

4 The ionization of water Water is both a weak acid and a weak base What does the double-headed arrow mean? Water plays an important role in acid and base chemistry. Water itself is both a weak acid and a weak base. A water molecule can split or ionize into H+ and OHions. Because the H+ ions immediately attach themselves to water molecules, the equation for the ionization of water is written as: 2H 2 O H 3 O + + OH- The double-headed arrow in the equation means that water, if left alone, is always in equilibrium with its ions. The rate at which water breaks down into ions is the same as the rate at which the ions re-form into water. However, water ionizes so slowly that most water molecules exist whole, not as ions. Figure 25.3:.Water ionizes into H+ and OH- ions. Therefore, it acts like both a weak acid and a weak base. Pure water has a neutral ph (ph 7) because the concentrations of H+ and OH- ions are equal. Examples of acid and base chemistry 432 play a role in digestion have many uses Many reactions, such as the ones that occur in your body, work best at specific ph values. For example, acids and bases are very important in the reactions involved in digesting food (see figure 25.1). As you may know, the stomach secretes hydrochloric acid (HCl), a strong acid (ph 1.4). The acidity of our stomachs is necessary to break down the protein molecules in our food so that they can be absorbed. A mucus lining in the stomach protects it from the acid produced. As food and digestive fluids leave the stomach, however, other organs in the digestive system also need to be protected from the acid. This is accomplished by two parts of the system the pancreas and liver. These two organs secrete bicarbonate to neutralize the stomach acid before it reaches other organs. The reactivity of acids and bases means that these chemicals have many uses. They react with each other and other chemicals. Metals and glass can be etched with corrosive acids. Lye (ph 13) is used to unclog drains, and sulfuric acid (ph 1) is used throughout industry. Millions of tons of sulfuric acid are produced each year (40 million tons in 1990). Its uses range from making rayon to cleaning impurities from gasoline. Figure 25.4: Carbon dioxide gas (CO 2 ) escaping from carbonated water. The CO 2 molecules are chains of three atoms, and the water molecules have a triangular shape. CO 2 makes soda fizzy and reacts with water to form carbonic acid, which gives the soda a sharp, or acidic, taste. This and other acids in soda, like phosphoric acid, can dissolve tooth enamel. Be sure to brush your teeth after drinking soda!

5 Electrolytes and nonelectrolytes Electrolytes conduct current Salt dissociates in water are electrolytes Non-electrolytes do not have ions and are not acidic or basic Current is the flow of charge. When a solution contains dissolved ions (charged particles), it can conduct current. Chemicals that conduct current when dissolved in water are called electrolytes. These chemicals form ions when dissolved. Ionic compounds, molecular compounds, and even atoms can contribute ions to a solution. When an ionic compound is dissolved in water, the polar ends of the water molecule attract the positive and negative ions in the solution. In previous sections, you learned how water dissolves table salt (NaCl). Recall that the attraction of the polar ends of the water molecule is strong enough to break the weak ionic bonds of NaCl. When an ionic compound is brought into solution by water it is said to dissociate. The term ionization is used if a molecular compound or atom forms an ion. For example, when NaCl dissolves in water we say it dissociates. When the element Na loses an electron, it ionizes to Na+. All acids and bases are electrolytes because they contribute ions to a solution. Some chemicals, like salt (NaCl), dissociate to form ions in solution but are not acidic or basic. Acids, bases, and salt water are examples of electrolytes. Other chemicals do not form ions when they are dissolved in solution. They are called non-electrolytes. Non-electrolytes are not acidic or basic. Sugar dissolved in water is an example of a non-electrolyte. Electrical appliances and water Because tap water contains small amounts of dissolved ions, it is an electrolyte. Remember that even a small amount of current is dangerous if it enters your body directly? Water provides a way for electric current to enter your body, so always take care when using electrical appliances near water! Electrolytes and your body When you perform a strenuous activity, your body cools itself by sweating. Sweat contains water and dissolved salts (or electrolytes) like sodium and potassium. Before, during, and after exercising, you can replenish fluids and your body s electrolytes by drinking diluted fruit juice, slightly salty water, or by consuming a sports drinks. The water in these fluids helps your body continue to cool itself so that you don t get overheated. By replacing electrolytes, you may be helping your body speed up resorption of fluids. Diluted fruit juice or a sports drink contains small amounts of carbohydrates to give your body the energy boost it may need during strenuous exercise. 433

6 The ph of substances you use or consume Many foods are acidic and many cleaning products are basic Table 25.1 contains a list of some common chemicals and their ph values. What do you notice about this list of substances? Where would you find acids in your kitchen? Where would you find bases? Table 25.1: The ph of some common chemicals. Household chemical Acid or base ph lemon juice acid 2 vinegar acid 3 soda water acid 4 baking soda base 8.5 bar soap base 10 ammonia base 11 It turns out that many of the foods we consume or use for cooking are acidic. On the other hand, many of our household cleaning products are basic. A ph indicator In the Investigation, you will be testing the ph of common chemicals using another item that you may find in your kitchen. You will measure ph using a ph indicator a chemical that changes color at different ph values. Common foods can also be used as ph indicators. In the Investigation, the indicator you will use is made from the juice of a red cabbage. Acids, bases, and taste Our taste buds are sensitive to acids and bases. We taste acids as sour and bases as bitter. Lemon juice is strongly acidic, and soap is strongly basic. Acids that are stronger than lemon juice and bases that are stronger than ammonia are so reactive that they can harm your skin and damage clothing. Figure 25.5: The ph scale showing common substances. 434

7 Health Perspective: ph and your blood It is very important for your blood ph to stay within the normal range. At higher or lower ph values, your body does not function properly. Fortunately, you can regulate the ph of your blood simply by breathing! Blood is a watery solution that contains many solutes including the dissolved gases carbon dioxide and oxygen. Carbon dioxide appears in your blood because it is produced by respiration. Recall that respiration is the combustion of sugar by your body. You breathe in oxygen to get this process going. The end products of this reaction are energy, water, and carbon dioxide. C 6 H 12 O 6 + 6O 2 6CO 2 + 6H 2 O + energy The rate at which you breathe controls the concentration of carbon dioxide in your blood. For example, if you hold your breath, more carbon dioxide enters your blood. If you hyperventilate, you blow off carbon dioxide, so that significantly less is in your blood. These two processes influence blood ph. The equation below illustrates how carbon dioxide dissolves in an aqueous (watery) solution like blood: CO 2 + H 2 O H 2 CO 3 H + + HCO - 3 carbon dioxide + water carbonic acid hydrogen ion + bicarbonate ion When CO 2 dissolves, H+ ions are produced in solution. Therefore, the more CO 2 in your blood, the more acidic your blood will become. If you breathe slowly, the added CO 2 makes your blood more acidic. However, if you breathe too often and too quickly (hyperventilating), the loss of CO 2 makes your blood more basic. You can offset this effect by breathing into a paper bag. This forces you to re-breathe carbon dioxide. When you breathe normally, your blood ph ranges between 7.35 and Figure 25.6: Some causes of low blood ph (acidosis) include holding your breath, excessive lactic acid produced during heavy exercise, and production of ketone acids because of fasting or having low levels of insulin (diabetes). High blood ph (alkalosis) can be caused by hyperventilating. Under normal conditions, your blood ph ranges between 7.35 and

Properties of Acids and Bases

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 information

3 Solutions of Acids and Bases

3 Solutions of Acids and Bases CHAPTER 3 3 Solutions of Acids and Bases SECTION Chemical Compounds BEFORE YOU READ After you read this section, you should be able to answer these questions: What are strong and weak acids? What are strong

More information

Chapter 17. How are acids different from bases? Acid Physical properties. Base. Explaining the difference in properties of acids and bases

Chapter 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 information

Acids, Bases, and ph

Acids, 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 information

CHAPTER 9. ANS: a. ANS: d. ANS: c. ANS: a. ANS: c

CHAPTER 9. ANS: a. ANS: d. ANS: c. ANS: a. ANS: c CHAPTER 9 1. Which one of the following is the acid in vinegar? a. acetic acid b. citric acid c. muriatic acid d. ascorbic acid 2. Which is a basic or alkaline substance? a. gastric fluid b. black coffee

More information

Acids, Bases and Concentrations

Acids, Bases and Concentrations 61 Chapter 7 Acids, Bases and Concentrations Thoughts or pictures of a shark usually evoke fear. But most sharks are not harmful to humans and shark attacks while dangerous and sometimes fatal are extremely

More information

Chemistry 52. Reacts with active metals to produce hydrogen gas. Have a slippery, soapy feeling. React with carbonates to produce CO 2

Chemistry 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 information

Chapter 9 Acids, Bases and Buffers in the Body Outline 9.1 Acids and Bases Definitions Acids

Chapter 9 Acids, Bases and Buffers in the Body Outline 9.1 Acids and Bases Definitions Acids Lecture Presentation Chapter 9 Acids, Bases and Buffers in the Body Julie Klare Fortis College Smyrna, GA Outline 9.1 Acids and Bases Definitions 9.2 Strong Acids and Bases 9.3 Chemical Equilibrium 9.4

More information

Letter to the Student... 5 Test-Taking Checklist... 6 Next Generation Sunshine State Standards Correlation Chart... 7

Letter to the Student... 5 Test-Taking Checklist... 6 Next Generation Sunshine State Standards Correlation Chart... 7 Table of Contents Letter to the Student..................................... 5 Test-Taking Checklist.................................... 6 Next Generation Sunshine State Standards Correlation Chart...

More information

How many ml of 0.250M potassium permangenate are needed to react with 3.36 g of iron(ii) sulfate?

How many ml of 0.250M potassium permangenate are needed to react with 3.36 g of iron(ii) sulfate? How many ml of 0.250M potassium permangenate are needed to react with 3.36 g of iron(ii) sulfate? 1 - Change the mass of iron(ii) sulfate to moles using the formula weight.of iron(ii) sulfate 2 - Change

More information

WATER, ph, ACIDS, BASES, AND BUFFERS

WATER, ph, ACIDS, BASES, AND BUFFERS COURSE READINESS ASSESSMENT FOR PHYSIOLOGY WATER, ph, ACIDS, BASES, AND BUFFERS Sections in this module I. Water is a polar molecule II. Properties of water III. ph IV. Acids and bases V. Buffers I. Water

More information

Experiment 16-Acids, Bases and ph

Experiment 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 information

Q1: 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 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 information

Acid 7 Base. 1. Describe two things hydrochloric acid does in your body system. 2. What does sodium hydrogencarbonate do in your body system?

Acid 7 Base. 1. Describe two things hydrochloric acid does in your body system. 2. What does sodium hydrogencarbonate do in your body system? Acids and Bases acid: a compound that, when dissolved in water, forms a solution with a ph less than 7 base: a compound that, when dissolved in water, forms a solution with a ph greater than 7 ph: the

More information

ACIDS AND BASES SAFETY PRECAUTIONS

ACIDS AND BASES SAFETY PRECAUTIONS ACIDS AND BASES Mild acids and bases are used in cooking (their reaction makes biscuits and bread rise). Acids such as those in our stomachs eat away at food or digest it. Strong acids and bases are used

More information

Syllabus OC18 Use litmus or a universal indicator to test a variety of solutions, and classify these as acidic, basic or neutral

Syllabus 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 information

Basic chemistry for A level Biology

Basic chemistry for A level Biology Basic chemistry for A level Biology Make a list of the missing words from the text please. Chose from this list; MISSING WORDS Neutrons, arrangement, carbon-14, charge, weak, alkaline, covalently, number,

More information

Chem101: General Chemistry Lecture 9 Acids and Bases

Chem101: 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 information

Chemistry Ch 9 Chemical Reactions Glencoe

Chemistry Ch 9 Chemical Reactions Glencoe Chemistry Ch 9 Chemical Reactions Glencoe Section 9.1 Reactions and Equations Chemical Reaction -is the process by which one or more substances are rearranged to form different substances. Five Evidences

More information

Chapter 6. Solution, Acids and Bases

Chapter 6. Solution, Acids and Bases Chapter 6 Solution, Acids and Bases Mixtures Two or more substances Heterogeneous- different from place to place Types of heterogeneous mixtures Suspensions- Large particles that eventually settle out

More information

Neutralizing an Acid and a Base

Neutralizing 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 information

Experiment 9 - Double Displacement Reactions

Experiment 9 - Double Displacement Reactions Experiment 9 - 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 information

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE 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 information

Experiment 8 - Double Displacement Reactions

Experiment 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 information

Table 1. give a slippery feel. produce a piercing pain in a wound. are colorless when placed in phenolphthalein (an indicator).

Table 1. give a slippery feel. produce a piercing pain in a wound. are colorless when placed in phenolphthalein (an indicator). Acid/Base Basics How does one define acids and bases? In chemistry, acids and bases have been defined differently by two sets of theories. One is the Arrhenius definition, which revolves around the idea

More information

EXPERIMENT 20: Determination of ph of Common Substances

EXPERIMENT 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 information

H 2 O + HNO 3 H 3 O + + NO 3

H 2 O + HNO 3 H 3 O + + NO 3 Properties Unit 12 Acids & Bases electrolytes sour taste turn litmus red react with metals to form 2 gas vinegar, soda, citrus fruits electrolytes bitter taste turn litmus blue slippery feel ammonia, lye,

More information

Nomenclature: How to Name Chemicals

Nomenclature: How to Name Chemicals Nomenclature: How to Name Chemicals Introduction Many of the chemicals we use at home have common names. Baking soda is used as a rising agent in cookies. Bleach is used to whiten our clothes. Ammonia

More information

Properties of Acids and Bases Identification and Classification

Properties of Acids and Bases Identification and Classification Properties of Acids and Bases Identification and Classification Introduction Acids and bases are useful reagents in the chemistry laboratory and play an important role in biology and nature. What are acids

More information

ACIDS, BASES AND SALTS

ACIDS, BASES AND SALTS Acids are those chemical substances which have a sour taste. Bases are those chemical substances which have a bitter taste. A salt is an ionic compound which dissociates to yield a positive ion other than

More information

6.8 Measuring the Acidity of Solutions Page 160

6.8 Measuring the Acidity of Solutions Page 160 6.8 Measuring the Acidity of Solutions Page 160 PRESCRIBED LEARNING OUTCOMES measure substances and solutions according to ph, solubility, and concentration KNOWLEDGE ph is the measure of the tendency

More information

Chemistry Unit Test Review

Chemistry 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 information

1. A mixture that contains more than one type of matter and is the same throughout is a mixture.

1. A mixture that contains more than one type of matter and is the same throughout is a mixture. 2nd Semester Benchmark Review Completion Complete each statement. 1. A mixture that contains more than one type of matter and is the same throughout is a mixture. 2. A mixture in which different samples

More information

Handout 6-A. The Ion Balancing Act of ph. Using Forensics: Wildlife Crime Scene!

Handout 6-A. The Ion Balancing Act of ph. Using Forensics: Wildlife Crime Scene! The Ion Balancing Act of ph Name Date We are affected every day by the ph of liquids in and around us. The food we eat and liquids we drink have ph levels, and our body organs require specific phs to keep

More information

20.2 Chemical Equations

20.2 Chemical Equations All of the chemical changes you observed in the last Investigation were the result of chemical reactions. A chemical reaction involves a rearrangement of atoms in one or more reactants to form one or more

More information

EXPERIMENT 10 Chemistry 110. Solutions Part 2 ACIDS, BASES, AND ELECTROLYTES

EXPERIMENT 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 information

Write the acid-base equilibria connecting all components in the aqueous solution. Now list all of the species present.

Write 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 information

CHEMISTRY: Identifying Acids and Bases with Red Cabbage Indicator

CHEMISTRY: Identifying Acids and Bases with Red Cabbage Indicator CHEMISTRY: Identifying Acids and Bases with Red Cabbage Indicator By Darby Sloss and Marianne Smith Edited by Anne Starace Abstract Chemistry is an important part of our lives. Kitchen Chemistry uses some

More information

Chemical Reactions in Water Ron Robertson

Chemical Reactions in Water Ron Robertson Chemical Reactions in Water Ron Robertson r2 f:\files\courses\1110-20\2010 possible slides for web\waterchemtrans.doc Properties of Compounds in Water Electrolytes and nonelectrolytes Water soluble compounds

More information

Chemical Reactions in Water

Chemical Reactions in Water Chemical Reactions in Water Ron Robertson r2 f:\files\courses\1110-20\2010 possible slides for web\waterchemtrans.doc Acids, Bases and Salts Acids dissolve in water to give H + ions. These ions attach

More information

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.

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. 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 information

CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS

CHEMICAL 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 information

Test Bank - Chapter 6 Multiple Choice

Test Bank - Chapter 6 Multiple Choice Test Bank - Chapter 6 The questions in the test bank cover the concepts from the lessons in Chapter 6. Select questions from any of the categories that match the content you covered with students. The

More information

not to be republished NCERT Acids, Bases and Salts CHAPTER 2 Multiple Choice Questions

not to be republished NCERT Acids, Bases and Salts CHAPTER 2 Multiple Choice Questions Multiple Choice Questions 1. What happens when a solution of an acid is mixed with a solution of a base in a test tube? (i) The temperature of the solution increases (ii) The temperature of the solution

More information

Topic 8 Acids and bases 6 hours

Topic 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 information

Suggested Problems: p. 625-627 #58, 59, 65, 69, 74, 80, 85, 86, 90, 92, 93, 98, 99

Suggested 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 information

Electrolysis This is when an electric current passes through an electrolyte.

Electrolysis This is when an electric current passes through an electrolyte. Conductors Metals and graphite are the only solids which conduct electricity, but no chemical change is involved. Liquid (melted) metals also conduct, but again there is no chemical change. Electrolytes

More information

ANSWER KEY. Acids, Bases, and Solutions. Chapter Project Worksheet 1 1. Answers will vary. Sample: cherries, blueberries,

ANSWER KEY. Acids, Bases, and Solutions. Chapter Project Worksheet 1 1. Answers will vary. Sample: cherries, blueberries, Chapter Project Worksheet 1 1. Answers will vary. Sample: cherries, blueberries, and grass 2. Answers will vary. Sample: Cut 5 g of cherries into small pieces and place in blender. Blend for two minutes,

More information

Chemistry 3202. Unit 2 Acids and Bases

Chemistry 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 information

Acid-Base Indicator Useful Indicators

Acid-Base Indicator Useful Indicators Chemistry 101 - H Acids and Bases This presentation was created by Professor Carl H. Snyder Chemistry Department University of Miami Coral Gables, FL 33124 CSnyder@miami.edu Chapter 10 - Acids and Bases

More information

CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS

CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS CHEMICAL DETERMINATION OF EVERYDAY HOUSEHOLD CHEMICALS Cautions: You will be using dangerous, caustic (corrosive) chemicals in this lab, so it is important that you are very careful with them. Wear gloves

More information

Notes: Acids and Bases

Notes: Acids and Bases Name Chemistry Pre-AP Notes: Acids and Bases Period I. Describing Acids and Bases A. Properties of Acids taste ph 7 Acids change color of an (e.g. blue litmus paper turns in the presence of an acid) React

More information

Acids and Bases. AND a widemouth container of the following solids:

Acids 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 information

- electrolytes: substances that dissolve in water to form charge-carrying solutions

- electrolytes: substances that dissolve in water to form charge-carrying solutions 111 Electrolytes and Ionic Theory - electrolytes: substances that dissolve in water to form charge-carrying solutions * Electrolytes form ions in solution - (ions that are mobile are able to carry charge!).

More information

Chapter 2: Atoms, Molecules & Life

Chapter 2: Atoms, Molecules & Life Chapter 2: Atoms, Molecules & Life What Are Atoms? An atom are the smallest unit of matter. Atoms are composed of Electrons = negatively charged particles. Neutrons = particles with no charge (neutral).

More information

Chapter 19: Acids and Bases Homework Packet (50 pts) Name: Score: / 50

Chapter 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 information

Acids and Bases HW PSI Chemistry

Acids 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 information

Chapter 2. The Chemistry of Life Worksheets

Chapter 2. The Chemistry of Life Worksheets Chapter 2 The Chemistry of Life Worksheets (Opening image courtesy of David Iberri, http://en.wikipedia.org/wiki/file:camkii.png, and under the Creative Commons license CC-BY-SA 3.0.) Lesson 2.1: Matter

More information

Chapter 4: Solution Stoichiometry Cont. Aqueous Solutions

Chapter 4: Solution Stoichiometry Cont. Aqueous Solutions Chapter 4: Solution Stoichiometry Cont. 1 Aqueous Solutions Molarity (dilution calculations, solution stoichiometry); Solubility and Solubility Rules Molecular, Ionic and Net Ionic Equations Precipitation

More information

The Molecules of Cells

The Molecules of Cells The Molecules of Cells Chapter 2 Introduction: Who Tends This Garden? Chemicals are the stuff that make up our bodies and those of other organisms They make up the physical environment as well The ordering

More information

Answer the following questions on notebook paper, to be collected and graded for correctness.

Answer the following questions on notebook paper, to be collected and graded for correctness. nswer the following questions on notebook paper, to be collected and graded for correctness. 1. Name the following binary acids: a. HCl hydrochloric acid b. HF hydrofluoric acid c. H 2 S hydrosulfuric

More information

Acids 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 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 information

Chapter 4 Three Major Classes of Chemical Reactions. As will likely come as no surprise, chemical reactions can be categorized in a variety of

Chapter 4 Three Major Classes of Chemical Reactions. As will likely come as no surprise, chemical reactions can be categorized in a variety of Chapter 4 Three Major Classes of Chemical Reactions As will likely come as no surprise, chemical reactions can be categorized in a variety of different ways, with nearly all reactions falling into more

More information

6) Which compound is manufactured in larger quantities in the U.S. than any other industrial chemical?

6) 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 information

Wherever chemical solutions are involved, ph matters. Some

Wherever chemical solutions are involved, ph matters. Some 47 Acids, Bases, and the ph Scale r e a d i n g Wherever chemical solutions are involved, ph matters. Some important chemical reactions, such as those involved in corrosion of iron or digestion of food,

More information

LESSON 23: Exploding Bags ESTIMATED TIME Setup: 5 minutes Procedure: 5 minutes

LESSON 23: Exploding Bags ESTIMATED TIME Setup: 5 minutes Procedure: 5 minutes LESSON 23: Exploding Bags ESTIMATED TIME Setup: 5 minutes Procedure: 5 minutes DESCRIPTION Combine vinegar and baking soda within a plastic bag to initiate a chemical reaction. OBJECTIVE This lesson demonstrates

More information

Acids and Bases: Cabbage Juice ph Indicator

Acids and Bases: Cabbage Juice ph Indicator Acids and Bases: Cabbage Juice ph Indicator Teacher Version * If printing the labs in black & white, be sure to print out a color version of the cabbage juice ph scale separately * Acids and bases are

More information

CHAPTER 16: ACIDS AND BASES

CHAPTER 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 information

Chapter 4 Notes - Types of Chemical Reactions and Solution Chemistry

Chapter 4 Notes - Types of Chemical Reactions and Solution Chemistry AP Chemistry A. Allan Chapter 4 Notes - Types of Chemical Reactions and Solution Chemistry 4.1 Water, the Common Solvent A. Structure of water 1. Oxygen's electronegativity is high (3.5) and hydrogen's

More information

9.5 ph and the ph Scale

9.5 ph and the ph Scale 9.5 ph and the ph Scale Living things prefer a constant ph. Normal blood ph is strictly regulated between 7.35 and 7.45. The ph of a solution is commonly measured either electronically by using an instrument

More information

Chemical reactions. Classifications Reactions in solution Ionic equations

Chemical reactions. Classifications Reactions in solution Ionic equations Chemical reactions Classifications Reactions in solution Ionic equations Learning objectives Distinguish between chemical and physical change Write and balance chemical equations Describe concepts of oxidation

More information

UNIT (6) ACIDS AND BASES

UNIT (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 information

Net Ionic Equations Making Sense of Chemical Reactions

Net Ionic Equations Making Sense of Chemical Reactions 14 Making Sense of Chemical Reactions OBJECTIVE Students will be able to write net ionic equations from balanced molecular equations. LEVEL Chemistry NATIONAL STANDARDS UCP.1, UCP.2, B.3 T E A C H E R

More information

Predict the products of neutralization reactions. 1. What are the two products of all neutralization reactions? a. Salt and water

Predict the products of neutralization reactions. 1. What are the two products of all neutralization reactions? a. Salt and water Predict the products of neutralization reactions. 1. What are the two products of all neutralization reactions? a. Salt and water Predict whether a neutral solution will results from a neutralization reaction.

More information

Final Assessment: Acids and Bases and the ph scale

Final Assessment: Acids and Bases and the ph scale Final Assessment: Acids and Bases and the ph scale In order to construct acid-base indicators using organic substances, it is first necessary to understand terms and concepts related to the ph scale. According

More information

Coral Reefs in Danger: Ocean Acidification Lesson by Bill Andrake

Coral Reefs in Danger: Ocean Acidification Lesson by Bill Andrake Coral Reefs in Danger: Ocean Acidification Lesson by Bill Andrake In this webisode, Jonathan narrates a comprehensive lesson about the biology of corals and the coral reef ecosystem in our tropical oceans.

More information

Strong Acids (Know These) Announcements & Agenda (02/23/07) Strengths of Acids/Bases - Ionization. Last Time: Last Time: nsted-lowry Acids & Bases

Strong Acids (Know These) Announcements & Agenda (02/23/07) Strengths of Acids/Bases - Ionization. Last Time: Last Time: nsted-lowry Acids & Bases Announcements & Agenda (0//07) You should be reading Ch 0 this weekend! Quiz Today! Open Review Sessions @ pm on Wed. Low attendance this week Last Time: Bronsted nsted-lowry Acids & Bases acids donate

More information

CHM1 Review for Exam 12

CHM1 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 information

Q1. The chart shows the processes involved in the manufacture of nitric acid from ammonia.

Q1. The chart shows the processes involved in the manufacture of nitric acid from ammonia. Chemistry C2 Foundation and Higher Questions Q1. The chart shows the processes involved in the manufacture of nitric acid from ammonia. (a) Complete the word equation for the reaction that takes place

More information

Grade 9 Science Unit: Atoms and Elements Topic 4: Periodic Table & Compounds

Grade 9 Science Unit: Atoms and Elements Topic 4: Periodic Table & Compounds Grade 9 Science Unit: Atoms and Elements Topic 4: Periodic Table & Compounds Topic Using the Periodic Table Metals, Non- Metals & Metalloids I can Explain and identify the periods of the Periodic Table.

More information

EXPERIMENT 4 Acid Strength

EXPERIMENT 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 information

Properties of Acids and Bases

Properties 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 information

About Science Prof Online PowerPoint Resources

About Science Prof Online PowerPoint Resources About Science Prof Online PowerPoint Resources Science Prof Online (SPO) is a free science education website that provides fully-developed Virtual Science Classrooms, science-related PowerPoints, articles

More information

Chapter 14: Acids and Bases

Chapter 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 information

12.1 How do sub-atomic particles help us to understand the structure of substances?

12.1 How do sub-atomic particles help us to understand the structure of substances? 12.1 How do sub-atomic particles help us to understand the structure of substances? Simple particle theory is developed in this unit to include atomic structure and bonding. The arrangement of electrons

More information

No Brain Too Small. Credits: Four

No Brain Too Small. Credits: Four No Brain Too Small Level 1 Science 2015 90944 Demonstrate understanding of aspects of acids and bases Credits: Four Achievement Achievement with Merit Achievement with Excellence Demonstrate understanding

More information

EXPERIMENT 10: Electrical Conductivity Chem 111

EXPERIMENT 10: Electrical Conductivity Chem 111 EXPERIMENT 10: Electrical Conductivity Chem 111 INTRODUCTION A. Electrical Conductivity A substance can conduct an electrical current if it is made of positively and negatively charged particles that are

More information

Chapter 7 Chemical Reactions

Chapter 7 Chemical Reactions Chemistry 25 Chapter 7 Chemical Reactions Chemical Reactions Reactions involve chemical changes in matter resulting in new substances. Reactions involve rearrangement and exchange of atoms to produce new

More information

1. Define and give an example of the following:

1. Define and give an example of the following: Name: KEY Date: / / HR: Section 1 Chemistry of Life CHAPTER 3 CELL PROCESSES REVIEW 1. Define and give an example of the following: a. Atoms invisible particles that make up all mater; made from protons,

More information

Colourful chemistry 1.0eng

Colourful chemistry 1.0eng Colourful chemistry 1.0eng Heureka, the Finnish Science Centre, www.heureka.fi Kati Tyystjärvi kati.tyystjarvi@heureka.fi General The purpose of this project is to familiarize students with acids and alkaline

More information

I. Definitions: Name: Period: Date: 1. Arrhenius (1887)- produce in aqueous solutions produce in aqueous solutions

I. Definitions: Name: Period: Date: 1. Arrhenius (1887)- produce in aqueous solutions produce in aqueous solutions Name: Period: Date: I. Definitions: 1. Arrhenius (1887)- produce in aqueous solutions produce in aqueous solutions 2. Bronsted-Lowry (1923) 3. Lewis (1923), so only allows for aqueous solutions only protic

More information

Chapter 4 Chemical Reactions

Chapter 4 Chemical Reactions Chapter 4 Chemical Reactions I) Ions in Aqueous Solution many reactions take place in water form ions in solution aq solution = solute + solvent solute: substance being dissolved and present in lesser

More information

6. A Six-Bottle Study of Ionic Compounds

6. A Six-Bottle Study of Ionic Compounds 6. A Six-Bottle Study of Ionic Compounds What you will accomplish in this experiment In last week s experiment, you observed a chemical change: a chemical reaction that resulted in a change in the composition,

More information

Factors that Affect the Rate of Dissolving and Solubility

Factors that Affect the Rate of Dissolving and Solubility Dissolving Factors that Affect the Rate of Dissolving and Solubility One very important property of a solution is the rate of, or how quickly a solute dissolves in a solvent. When dissolving occurs, there

More information

Chapter 6 Student Reading

Chapter 6 Student Reading Chapter 6 Student Reading What is a chemical reaction? There are many common examples of chemical reactions. For instance, chemical reactions happen when baking cookies and in your digestive system when

More information

(Almost) Everything You NEED in Chemistry

(Almost) Everything You NEED in Chemistry (Almost) Everything You NEED in Chemistry An atom consists of a central portion, the NUCLEUS (made up of Protons and Neutrons) and Electrons which are found outside the nucleus. An uncharged atom has an

More information

Acids and Alkalis. you will learn. What. Sour taste. The opposite of an acid. Telling them apart. Cancelling out

Acids and Alkalis. you will learn. What. Sour taste. The opposite of an acid. Telling them apart. Cancelling out 4 Acids and What you will learn Sour taste The opposite of an acid Telling them apart Cancelling out 33 Acids and 4a Sour taste In grade 6, you have studied that there are many ways that you could classify

More information

Acids, Bases and Salts

Acids, Bases and Salts Acids, Bases and Salts 2 HAPTER Tips and Tricks Acids are sour in taste and bases are bitter in taste. Indicators are chemical substances which give different colours in acidic and basic solutions. If

More information

Chemical bonds between atoms involve electrons.

Chemical bonds between atoms involve electrons. Chapter 6, Section 2 Key Concept: Chemical bonds hold compounds together. BEFORE, you learned Elements combine to form compounds Electrons are located in a cloud around the nucleus Atoms can lose or gain

More information

Robert Boyle. Properties of Acids and Bases According to Boyle. According to Boyle. According to Boyle

Robert Boyle. Properties of Acids and Bases According to Boyle. According to Boyle. According to Boyle Properties of Acids and Bases According to Boyle In 1661 Robert Boyle summarized the properties of acids as follows: 1. Acids have a sour taste. 2. Acids are corrosive. 3. Acids change the color of certain

More information