6 Reactions in Aqueous Solutions

Size: px
Start display at page:

Download "6 Reactions in Aqueous Solutions"

Transcription

1 6 Reactions in Aqueous Solutions Water is by far the most common medium in which chemical reactions occur naturally. It is not hard to see this: 70% of our body mass is water and about 70% of the surface of the earth is covered in water. The types of reactions in aqueous (water) medium that will be studied are as follow: 1. Precipitation Reactions. Acid-Base Reactions. Oxidation-Reduction Reactions (Special Case of the Reaction of Metals with Nonmetals) Recall that a solution is a homogeneous (uniform) mixture. A solution consists of two generic components: Solute the component (compound) that is in minor quantities; and Solvent the component that is in major quantity. Aqueous solutions then have water as the solvent. 6.1 Precipitation Reactions Precipitation reactions are those reactions in which two aqueous solutions, when mixed, react to form a solid. The solid thus formed is known as a precipitate. Thus, a precipitate is an insoluble solid (recall that an insoluble substance is one which does not dissolve). Indeed, if a solid that forms is soluble, then as soon as it forms it would dissolve back into solution so if a solid is soluble, it cannot, in general, be a precipitate. We have defined precipitates as insoluble solids. More specifically, we know that precipitates are insoluble ionic compounds. We must now ask what the mechanism for precipitation is. When an ionic substance is dissolved in water, we indicate this by appending an (aq) after the formula of the compound. Thus, for example, NaCl (aq) designates an aqueous solution of sodium chloride, Fe(NO ) (aq) designates an aqueous solution of iron (III) nitrite and so on. It is known that when an ionic substance dissolves in water it dissociates into its component ions. The evidence for this comes from electrical conductivity studies: Electrical current arises from the movement of charged substances Water does not conduct electricity, therefore it has no ions itself (this is actually a false assertion, but the concentration of ions in pure water is small) Thus, if an aqueous solution conducts electricity, it must contain charged substances (ions) that are free to move these ions can only come from an ionic solute (since we have made the assertion that water itself does not provide ions). For example, when NaCl is dissolved in water, there will be, in principle, no unit of NaCl found anywhere in the aqueous solution. Rather, we will see a soup consisting of Na + ions and Cl ions floating around. Although this is not regarded as a conventional reaction, we may write the process in the form of a chemical equation: NaCl (aq) Na + (aq) + Cl (aq) The (aq) attached to an ionic substance always means the component ions in the correct proportions, and that the ionic substance is soluble. NaCl (aq) means the same as Na + (aq) + Cl (aq) It is thus very important to recognize ionic compounds and to know what the component ions are. page 8

2 Ionic Compound Ions in Solution copper (II) sulphate CuSO (aq) Means Cu + (aq) and SO (aq) Barium nitrate Ba(NO ) (aq) Means Ba + (aq) and NO (aq) Potassium hydroxide KOH (aq) Means K + (aq) and OH (aq) Sodium hydrogen carbonate NaHCO (aq) Means Na + (aq) and HCO (aq) Ammonium dihydrogen phosphite (NH )H PO (aq) Means NH + (aq) and HPO (aq) What happens when two different aqueous solutions are mixed? Let us look at the specific example of a solution of an aqueous solution of sodium chloride mixed with an aqueous solution of silver nitrate. We know that both are ionic. (How?). Thus: NaCl (aq) Na + (aq) + Cl (aq) and AgNO (aq) Ag + (aq) + NO (aq) Na + (aq) and Cl (aq) Ag + (aq) and NO (aq) What we have now is a soup consisting of Na +, Cl, Ag + and NO floating around in water. These atoms are bouncing around the container colliding with each other. If Na + ions collide with other Na + ions, they will repel each other (they have the same charge). Likewise, if Ag + ions collide with Na + ions or other Ag + ions, they will repel each other. Similarly, any combination of collisions between anions will be repulsive. page 9

3 If the Na + ions collide with Cl, they will attract each other to form NaCl. However, since NaCl is soluble, it will immediately break back up into ions. A similar situation arises when Ag + collides with NO ions. Thus the only new things that can happen is for Na + ions to collide with NO ions to form NaNO and for Ag + to collide with Cl to form AgCl. It is an experimental fact that NaNO is soluble therefore it cannot form a precipitate; it is also known experimentally that AgCl is insoluble, therefore it will form a precipitate. Complete Molecular Equation NaCl (aq) + AgNO (aq) NaNO (aq) + AgCl (s) Na + (aq) + Cl (aq) + Complete Ag + (aq) + NO (aq) Na + (aq) + NO (aq) + AgCl (s) Ionic Equation Note that in the complete ionic equation, Na + (aq) and NO (aq) appear on both sides of the equation. This means that these two ions merely serve to ensure that overall, all charges are balanced. They serve no other function in the chemical reaction. Ions which do not participate in the chemical equation are known as spectator ions. Spectator ions are ions that appear on both sides of the complete ionic equation. If the spectator ions are cancelled as if they were variables in an algebraic equation, then we are left with the net ionic equation: Ag + (aq) + Cl (aq) AgCl (s) The net ionic equation describes the basic chemical process that is occurring by cutting out all nonessential information. For the following reactions, write the complete molecular equation, the complete ionic equation and the net ionic equation. Identify the spectator ions. e.g. BaCl (aq) +Na SO (aq) Step 1: Write out the ions in the reactants. Step : Ba + (aq) + Cl (aq) + Na + (aq) + SO? Examine all collisions that can occur and disregard those that cannot lead to a reaction. [Ba + (aq) + Cl (aq)] + [ Na + (aq) + Step : SO (aq)] [Ba + (aq) + SO (aq)] + [ Na + (aq) + Cl (aq)] Balance the charges on the product side, being sure to balance them on the reactant side also. Note that you must be careful in doing this by paying attention to which chemical produced which ions. Put the complete product molecules together. [Ba + (aq) + Cl (aq)] + [ Na + (aq) + SO (aq)] BaSO + NaCl Step : From your knowledge of solubilities, determine which (if any) of the products will form a precipitate. Recall that a precipitate is an insoluble solid. Ba + (aq) + Cl (aq)] + [ Na + (aq) + SO (aq)] BaSO (s) + NaC l(aq) Step 5: Recombine the reactant side ions to give the complete molecular equation. Step 6: BaCl (aq) +Na SO (aq) BaSO (s) + NaC l(aq) Write the complete ionic equation Ba + (aq) + Cl (aq) + Na+ (aq) + Step 7: SO (aq) BaSO (s) + Na + (aq) + Cl (aq) Cancel off the spectator ions and write the net ionic equation Ba + (aq) + SO (aq) BaSO (s) page 50

4 Solubility Rules for Some Common Salts in Water Note well: When an insoluble salt (ionic compound) forms when two or more solutions are mixed, then the substance will precipitate out of solution. If the salt is soluble no precipitate will form. 1. Most nitrate ( NO )salts are soluble.. Most salts containing the alkali metal ions (Li +, Na +, K +, Cs +, Rb + + ) and the ammonium ion ( NH ) are soluble.. Most chloride, bromide and iodide salts are soluble. Notable exceptions: Salts containing the ions Ag +, Pb + + and Hg.. Most sulfate salts ( SO ) are soluble. Notable exceptions: CaSO, BaSO, PbSO and Hg SO. 5. Most hydroxide salts (OH )are only slightly soluble. The important soluble hydroxides are NaOH and KOH. The Group IIA hydroxides are marginally soluble. S 6. Most sulphide ( ), carbonate ( CO ), chromate ( ) and phosphate salts ( ) are CrO PO only slightly soluble. These solubility rules must be memorized. They will be used to predict whether a precipitate will form. Exercises: Fe(NO ) (aq) + NaOH (aq) (NH ) PO (aq) + AlCl (aq) NiCl (aq) + Na CO (aq) Pb(NO ) (aq) + NaI (aq) Precipitation reactions are sometimes known as double displacement reactions because two ions exchange with each other. Schematically: AB + XY AY + XB Double Exchange That is, cation A exchanges places with cation X and anion B exchanges with anion Y. page 51

5 6. Acids and Bases Arrhenius Definitions: Acids: Substances which, when dissolved in water, produce H +. Bases: Substances which, when dissolved in water produce OH. Strong acids and strong bases are acids that are excellent conductors of electricity. The list of strong acids (to be memorized) is: HCl, HBr, HI, HNO, H SO, and HClO The strong bases are: the alkali metal hydroxides and the alkaline earth hydroxides (even though these latter are only sparingly soluble Dissociation of Acids As with other ionic substances, acids dissociate into their component ions when dissolve in water. However, the dissociation involves the removal of only one of the protons to produce, H + and the conjugate acid anion. Examples: H SO (aq) H + (aq) + HSO (aq) NOT [H SO (aq) H + (aq) + SO (aq) ] H PO (aq) H + (aq) + H S (aq) H + (aq) + HS (aq) HPO (aq) Obviously this is not an issue for monoprotic acids (acids having only one ionizable proton, e.g., HCl, HNO etc.) 6.. Acid-Base Reactions Acid-Base reactions, reactions between acids and bases, are sometimes referred to as neutralization reactions. The product of neutralization reactions are always a salt (an ionic compound) and water. e.g. HCl (aq) + NaOH (aq) [H + (aq) + Cl (aq)] + [Na + (aq) + OH (aq)] NaCl (aq) + H O (l) Double Exchange Complete Molecular Equation: HCl (aq) + NaOH (aq) NaCl (aq) + H O (l) Complete Ionic Equation: [H + (aq) + Cl (aq)] + [Na + (aq) + OH (aq)] Na + (aq) Cl (aq) + H O (l) Net Ionic Equation: H + (aq) + OH (aq)] H O (l) This is the net ionic equation for all acid-base reactions e.g. H SO (aq) + NaOH (aq) Ans: H SO (aq) + NaOH (aq) H O (l) + Na SO (aq) Note that Acid-Base reactions are double displacement reactions. page 5

6 6. Oxidation Reduction Reactions In the double displacement reactions discussed before (precipitation and acid-base reactions), we see a transfer of ions. Oxidation-Reduction reactions (Redox reactions) there is a transfer of electrons. Let us examine the reaction of sodium with chlorine. Na (s) + Cl (g) NaCl (s) Here, initially the oxidation number of Na = 0 and of Cl = 0 on the reactant side of the equation. On the product side, NaCl is formed from the attraction of Na + and Cl ions. Clearly, in the process of forming NaCl from its elements, sodium has lost an electron and chlorine has gained an electron: Na Na + + e Cl + e Cl Thus it can be observed that NaCl forms because of a transfer of electrons from sodium to chlorine. In the process, sodium changes its oxidation state from 0 to +1, whereas chlorine changes its oxidation state from 0 to 1. The change in oxidation state requires a transfer of electrons. Oxidation is defined to be the loss of electrons. The substance becomes more positive. Reduction is defined to be the gain of electrons. The substance becomes more negative. Thus we see in the above reactions that: Sodium is oxidized Chlorine is reduced. ************************ For all reactions, you should always check the oxidation numbers of the reactants and of product. If there is a change of oxidation state then the reaction is a redox reaction. If you can observe that the reaction is a double displacement or an acid base reaction, it is not necessary to do this double displacement (precipitationand acid-base reactions) are never redox reactions also. 6. Other Ways of Classifying Chemical Reactions There are several other ways of classifying chemical reactions. Very often, a particular reaction can be characterized in more than one ways. Three of those ways will be shown below Combustion Reactions Combustion reactions usually refer to chemical reaction with molecular oxygen to form oxides (other substances, such as Cl, will also support combustion but such cases are not often considered). Examples: The combustion of magnesium: Mg(s) + O (g) MgO (s) The combustion of propane: C H 8 (g) + 5 O (g) CO (g) + H O (l) Note: 1. Organic molecules are molecules that are composed of at least C and H atoms. Their combustion products are always CO and H O.. Combustion reactions are also redox reactions. page 5

7 6.. Synthesis Reactions Synthesis reactions are reactions that produce more products that are more complex than the reactants. Examples are: Mg(s) + O (g) MgO (s) H (g) + O (g) H O (l) CH (g) C H 6 (g) + H (g) Note that each of these can also be classified in other ways. The three examples for example are also redox reactions; the first two are combustion reactions. 6.. Decomposition Reactions Reactions that result in products that are simpler than the reactants are termed decomposition reactions. Examples include: CO (g) C (s) + O (g) C H (g) + O (g) CO (g) + H O (l) Note once more that reactions can be classified in more than one way. page 5

Chemical Equations. Chemical Equations. Chemical reactions describe processes involving chemical change

Chemical Equations. Chemical Equations. Chemical reactions describe processes involving chemical change Chemical Reactions Chemical Equations Chemical reactions describe processes involving chemical change The chemical change involves rearranging matter Converting one or more pure substances into new pure

More information

Writing and Balancing Chemical Equations

Writing and Balancing Chemical Equations Name Writing and Balancing Chemical Equations Period When a substance undergoes a chemical reaction, chemical bonds are broken and new bonds are formed. This results in one or more new substances, often

More information

Experiment 1 Chemical Reactions and Net Ionic Equations

Experiment 1 Chemical Reactions and Net Ionic Equations Experiment 1 Chemical Reactions and Net Ionic Equations I. Objective: To predict the products of some displacement reactions and write net ionic equations. II. Chemical Principles: A. Reaction Types. Chemical

More information

Chapter 7: Chemical Reactions

Chapter 7: Chemical Reactions Chapter 7 Page 1 Chapter 7: Chemical Reactions A chemical reaction: a process in which at least one new substance is formed as the result of a chemical change. A + B C + D Reactants Products Evidence that

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

Chapter 8: Chemical Equations and Reactions

Chapter 8: Chemical Equations and Reactions Chapter 8: Chemical Equations and Reactions I. Describing Chemical Reactions A. A chemical reaction is the process by which one or more substances are changed into one or more different substances. A chemical

More information

Balancing Chemical Equations Worksheet

Balancing Chemical Equations Worksheet Balancing Chemical Equations Worksheet Student Instructions 1. Identify the reactants and products and write a word equation. 2. Write the correct chemical formula for each of the reactants and the products.

More information

2. DECOMPOSITION REACTION ( A couple have a heated argument and break up )

2. DECOMPOSITION REACTION ( A couple have a heated argument and break up ) TYPES OF CHEMICAL REACTIONS Most reactions can be classified into one of five categories by examining the types of reactants and products involved in the reaction. Knowing the types of reactions can help

More information

Aqueous Ions and Reactions

Aqueous Ions and Reactions Aqueous Ions and Reactions (ions, acids, and bases) Demo NaCl(aq) + AgNO 3 (aq) AgCl (s) Two clear and colorless solutions turn to a cloudy white when mixed Demo Special Light bulb in water can test for

More information

1. When the following equation is balanced, the coefficient of Al is. Al (s) + H 2 O (l)? Al(OH) 3 (s) + H 2 (g)

1. When the following equation is balanced, the coefficient of Al is. Al (s) + H 2 O (l)? Al(OH) 3 (s) + H 2 (g) 1. When the following equation is balanced, the coefficient of Al is. Al (s) + H 2 O (l)? Al(OH) (s) + H 2 (g) A) 1 B) 2 C) 4 D) 5 E) Al (s) + H 2 O (l)? Al(OH) (s) + H 2 (g) Al (s) + H 2 O (l)? Al(OH)

More information

stoichiometry = the numerical relationships between chemical amounts in a reaction.

stoichiometry = the numerical relationships between chemical amounts in a reaction. 1 REACTIONS AND YIELD ANSWERS stoichiometry = the numerical relationships between chemical amounts in a reaction. 2C 8 H 18 (l) + 25O 2 16CO 2 (g) + 18H 2 O(g) From the equation, 16 moles of CO 2 (a greenhouse

More information

NAMING QUIZ 3 - Part A Name: 1. Zinc (II) Nitrate. 5. Silver (I) carbonate. 6. Aluminum acetate. 8. Iron (III) hydroxide

NAMING QUIZ 3 - Part A Name: 1. Zinc (II) Nitrate. 5. Silver (I) carbonate. 6. Aluminum acetate. 8. Iron (III) hydroxide NAMING QUIZ 3 - Part A Name: Write the formulas for the following compounds: 1. Zinc (II) Nitrate 2. Manganese (IV) sulfide 3. Barium permanganate 4. Sulfuric acid 5. Silver (I) carbonate 6. Aluminum acetate

More information

UNIT (4) CALCULATIONS AND CHEMICAL REACTIONS

UNIT (4) CALCULATIONS AND CHEMICAL REACTIONS UNIT (4) CALCULATIONS AND CHEMICAL REACTIONS 4.1 Formula Masses Recall that the decimal number written under the symbol of the element in the periodic table is the atomic mass of the element. 1 7 8 12

More information

Steps for balancing a chemical equation

Steps for balancing a chemical equation The Chemical Equation: A Chemical Recipe Dr. Gergens - SD Mesa College A. Learn the meaning of these arrows. B. The chemical equation is the shorthand notation for a chemical reaction. A chemical equation

More information

Chapter 6 Notes Science 10 Name:

Chapter 6 Notes Science 10 Name: 6.1 Types of Chemical Reactions a) Synthesis (A + B AB) Synthesis reactions are also known as reactions. When this occurs two or more reactants (usually elements) join to form a. A + B AB, where A and

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

Experiment 5. Chemical Reactions A + X AX AX A + X A + BX AX + B AZ + BX AX + BZ

Experiment 5. Chemical Reactions A + X AX AX A + X A + BX AX + B AZ + BX AX + BZ Experiment 5 Chemical Reactions OBJECTIVES 1. To observe the various criteria that are used to indicate that a chemical reaction has occurred. 2. To convert word equations into balanced inorganic chemical

More information

Molarity of Ions in Solution

Molarity of Ions in Solution APPENDIX A Molarity of Ions in Solution ften it is necessary to calculate not only the concentration (in molarity) of a compound in aqueous solution but also the concentration of each ion in aqueous solution.

More information

Chemistry Themed. Types of Reactions

Chemistry Themed. Types of Reactions Chemistry Themed Types of Reactions 1 2 Chemistry in the Community-2015-2016 Types of Reactions Date In-Class Assignment Homework T 10/20 TEST on Reactivity of Metals and Redox None W 10/21 Late Start

More information

Aqueous Solutions. Water is the dissolving medium, or solvent. Some Properties of Water. A Solute. Types of Chemical Reactions.

Aqueous Solutions. Water is the dissolving medium, or solvent. Some Properties of Water. A Solute. Types of Chemical Reactions. Aqueous Solutions and Solution Stoichiometry Water is the dissolving medium, or solvent. Some Properties of Water Water is bent or V-shaped. The O-H bonds are covalent. Water is a polar molecule. Hydration

More information

Name: Class: Date: 2 4 (aq)

Name: Class: Date: 2 4 (aq) Name: Class: Date: Unit 4 Practice Test Multiple Choice Identify the choice that best completes the statement or answers the question. 1) The balanced molecular equation for complete neutralization of

More information

NET IONIC EQUATIONS. A balanced chemical equation can describe all chemical reactions, an example of such an equation is:

NET IONIC EQUATIONS. A balanced chemical equation can describe all chemical reactions, an example of such an equation is: NET IONIC EQUATIONS A balanced chemical equation can describe all chemical reactions, an example of such an equation is: NaCl + AgNO 3 AgCl + NaNO 3 In this case, the simple formulas of the various reactants

More information

Stoichiometry and Aqueous Reactions (Chapter 4)

Stoichiometry and Aqueous Reactions (Chapter 4) Stoichiometry and Aqueous Reactions (Chapter 4) Chemical Equations 1. Balancing Chemical Equations (from Chapter 3) Adjust coefficients to get equal numbers of each kind of element on both sides of arrow.

More information

WRITING CHEMICAL FORMULA

WRITING CHEMICAL FORMULA WRITING CHEMICAL FORMULA For ionic compounds, the chemical formula must be worked out. You will no longer have the list of ions in the exam (like at GCSE). Instead you must learn some and work out others.

More information

Chemistry 51 Chapter 8 TYPES OF SOLUTIONS. A solution is a homogeneous mixture of two substances: a solute and a solvent.

Chemistry 51 Chapter 8 TYPES OF SOLUTIONS. A solution is a homogeneous mixture of two substances: a solute and a solvent. TYPES OF SOLUTIONS A solution is a homogeneous mixture of two substances: a solute and a solvent. Solute: substance being dissolved; present in lesser amount. Solvent: substance doing the dissolving; present

More information

Balancing Chemical Equations Practice

Balancing Chemical Equations Practice Science Objectives Students will describe what reactants and products in a chemical equation mean. Students will explain the difference between coefficients and subscripts in chemical equations. Students

More information

Chapter 5. Chemical Reactions and Equations. Introduction. Chapter 5 Topics. 5.1 What is a Chemical Reaction

Chapter 5. Chemical Reactions and Equations. Introduction. Chapter 5 Topics. 5.1 What is a Chemical Reaction Introduction Chapter 5 Chemical Reactions and Equations Chemical reactions occur all around us. How do we make sense of these changes? What patterns can we find? 1 2 Copyright The McGraw-Hill Companies,

More information

H 2 + O 2 H 2 O. - Note there is not enough hydrogen to react with oxygen - It is necessary to balance equation.

H 2 + O 2 H 2 O. - Note there is not enough hydrogen to react with oxygen - It is necessary to balance equation. CEMICAL REACTIONS 1 ydrogen + Oxygen Water 2 + O 2 2 O reactants product(s) reactant substance before chemical change product substance after chemical change Conservation of Mass During a chemical reaction,

More information

4.1 Aqueous Solutions. Chapter 4. Reactions in Aqueous Solution. Electrolytes. Strong Electrolytes. Weak Electrolytes

4.1 Aqueous Solutions. Chapter 4. Reactions in Aqueous Solution. Electrolytes. Strong Electrolytes. Weak Electrolytes Chapter 4 Reactions in Aqueous Solution 4.1 Aqueous Solutions Solution homogeneous mixture of 2 or more substances Solute the substance present in a smaller amount (usually solid in Chap. 4) Solvent the

More information

David A. Katz Chemist, Educator, Science Communicator, and Consultant Department of Chemistry, Pima Community College

David A. Katz Chemist, Educator, Science Communicator, and Consultant Department of Chemistry, Pima Community College WRITING CHEMICAL EQUATIONS 2004, 2002, 1989 by David A. Katz. All rights reserved. Permission for classroom used provided original copyright is included. David A. Katz Chemist, Educator, Science Communicator,

More information

Tutorial 4 SOLUTION STOICHIOMETRY. Solution stoichiometry calculations involve chemical reactions taking place in solution.

Tutorial 4 SOLUTION STOICHIOMETRY. Solution stoichiometry calculations involve chemical reactions taking place in solution. T-27 Tutorial 4 SOLUTION STOICHIOMETRY Solution stoichiometry calculations involve chemical reactions taking place in solution. Of the various methods of expressing solution concentration the most convenient

More information

Aqueous Chemical Reactions

Aqueous Chemical Reactions Name: Date: Lab Partners: Lab section: Aqueous Chemical Reactions The purpose of this lab is to introduce you to three major categories of reactions that occur in aqueous solutions: precipitation reactions,

More information

Formulae, stoichiometry and the mole concept

Formulae, stoichiometry and the mole concept 3 Formulae, stoichiometry and the mole concept Content 3.1 Symbols, Formulae and Chemical equations 3.2 Concept of Relative Mass 3.3 Mole Concept and Stoichiometry Learning Outcomes Candidates should be

More information

Chemistry B11 Chapter 4 Chemical reactions

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

More information

Writing Chemical Equations

Writing Chemical Equations Writing Chemical Equations Chemical equations for solution reactions can be written in three different forms; molecular l equations, complete ionic i equations, and net ionic equations. In class, so far,

More information

Chemical Equations and Chemical Reactions. Chapter 8.1

Chemical Equations and Chemical Reactions. Chapter 8.1 Chemical Equations and Chemical Reactions Chapter 8.1 Objectives List observations that suggest that a chemical reaction has taken place List the requirements for a correctly written chemical equation.

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

PART I: MULTIPLE CHOICE (30 multiple choice questions. Each multiple choice question is worth 2 points)

PART I: MULTIPLE CHOICE (30 multiple choice questions. Each multiple choice question is worth 2 points) CHEMISTRY 123-07 Midterm #1 Answer key October 14, 2010 Statistics: Average: 74 p (74%); Highest: 97 p (95%); Lowest: 33 p (33%) Number of students performing at or above average: 67 (57%) Number of students

More information

Periodic Table, Valency and Formula

Periodic Table, Valency and Formula Periodic Table, Valency and Formula Origins of the Periodic Table Mendelѐѐv in 1869 proposed that a relationship existed between the chemical properties of elements and their atomic masses. He noticed

More information

Moles. Balanced chemical equations Molar ratios Mass Composition Empirical and Molecular Mass Predicting Quantities Equations

Moles. Balanced chemical equations Molar ratios Mass Composition Empirical and Molecular Mass Predicting Quantities Equations Moles Balanced chemical equations Molar ratios Mass Composition Empirical and Molecular Mass Predicting Quantities Equations Micro World atoms & molecules Macro World grams Atomic mass is the mass of an

More information

CHAPTER 5: MOLECULES AND COMPOUNDS

CHAPTER 5: MOLECULES AND COMPOUNDS CHAPTER 5: MOLECULES AND COMPOUNDS Problems: 1-6, 9-13, 16, 20, 31-40, 43-64, 65 (a,b,c,e), 66(a-d,f), 69(a-d,f), 70(a-e), 71-78, 81-82, 87-96 A compound will display the same properties (e.g. melting

More information

Solution a homogeneous mixture = A solvent + solute(s) Aqueous solution water is the solvent

Solution a homogeneous mixture = A solvent + solute(s) Aqueous solution water is the solvent Solution a homogeneous mixture = A solvent + solute(s) Aqueous solution water is the solvent Water a polar solvent: dissolves most ionic compounds as well as many molecular compounds Aqueous solution:

More information

Chapter 11. Electrochemistry Oxidation and Reduction Reactions. Oxidation-Reduction Reactions. Oxidation-Reduction Reactions

Chapter 11. Electrochemistry Oxidation and Reduction Reactions. Oxidation-Reduction Reactions. Oxidation-Reduction Reactions Oxidation-Reduction Reactions Chapter 11 Electrochemistry Oxidation and Reduction Reactions An oxidation and reduction reaction occurs in both aqueous solutions and in reactions where substances are burned

More information

Chemistry: Chemical Equations

Chemistry: Chemical Equations Chemistry: Chemical Equations Write a balanced chemical equation for each word equation. Include the phase of each substance in the equation. Classify the reaction as synthesis, decomposition, single replacement,

More information

CHEMICAL REACTIONS. Chemistry 51 Chapter 6

CHEMICAL REACTIONS. Chemistry 51 Chapter 6 CHEMICAL REACTIONS A chemical reaction is a rearrangement of atoms in which some of the original bonds are broken and new bonds are formed to give different chemical structures. In a chemical reaction,

More information

General Chemistry II Chapter 20

General 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

1. Read P. 368-375, P. 382-387 & P. 429-436; P. 375 # 1-11 & P. 389 # 1,7,9,12,15; P. 436 #1, 7, 8, 11

1. Read P. 368-375, P. 382-387 & P. 429-436; P. 375 # 1-11 & P. 389 # 1,7,9,12,15; P. 436 #1, 7, 8, 11 SCH3U- R.H.KING ACADEMY SOLUTION & ACID/BASE WORKSHEET Name: The importance of water - MAKING CONNECTION READING 1. Read P. 368-375, P. 382-387 & P. 429-436; P. 375 # 1-11 & P. 389 # 1,7,9,12,15; P. 436

More information

MOLARITY = (moles solute) / (vol.solution in liter units)

MOLARITY = (moles solute) / (vol.solution in liter units) CHEM 101/105 Stoichiometry, as applied to Aqueous Solutions containing Ionic Solutes Lect-05 MOLES - a quantity of substance. Quantities of substances can be expressed as masses, as numbers, or as moles.

More information

I N V E S T I C E D O R O Z V O J E V Z D Ě L Á V Á N Í CHEMICAL REACTIONS

I N V E S T I C E D O R O Z V O J E V Z D Ě L Á V Á N Í CHEMICAL REACTIONS Chemical reaction = process during which original substances change to new substances, reactants turn to... The bonds of reactants... and new bonds are... The classification of reactions: 1. Classification

More information

Reactions in Aqueous Solution

Reactions in Aqueous Solution CHAPTER 7 1. Water is the most universal of all liquids. Water has a relatively large heat capacity and a relatively large liquid range, which means it can absorb the heat liberated by many reactions while

More information

Stoichiometry Review

Stoichiometry Review Stoichiometry Review There are 20 problems in this review set. Answers, including problem set-up, can be found in the second half of this document. 1. N 2 (g) + 3H 2 (g) --------> 2NH 3 (g) a. nitrogen

More information

Santa Monica College Chemistry 11

Santa Monica College Chemistry 11 Types of Reactions Objectives The objectives of this laboratory are as follows: To perform and observe the results of a variety of chemical reactions. To become familiar with the observable signs of chemical

More information

Solution. Practice Exercise. Concept Exercise

Solution. Practice Exercise. Concept Exercise Example Exercise 8.1 Evidence for a Reaction Which of the following is experimental evidence for a chemical reaction? (a) Pouring vinegar on baking soda gives foamy bubbles. (b) Mixing two solutions produces

More information

Nomenclature and the Periodic Table To name compounds and to determine molecular formulae from names a knowledge of the periodic table is helpful.

Nomenclature and the Periodic Table To name compounds and to determine molecular formulae from names a knowledge of the periodic table is helpful. Nomenclature and the Periodic Table To name compounds and to determine molecular formulae from names a knowledge of the periodic table is helpful. Atomic Number = number of protons Mass Number = number

More information

W1 WORKSHOP ON STOICHIOMETRY

W1 WORKSHOP ON STOICHIOMETRY INTRODUCTION W1 WORKSHOP ON STOICHIOMETRY These notes and exercises are designed to introduce you to the basic concepts required to understand a chemical formula or equation. Relative atomic masses of

More information

Monatomic Ions. A. Monatomic Ions In order to determine the charge of monatomic ions, you can use the periodic table as a guide:

Monatomic Ions. A. Monatomic Ions In order to determine the charge of monatomic ions, you can use the periodic table as a guide: Monatomic Ions Ions are atoms that have either lost or gained electrons. While atoms are neutral, ions are charged particles. A loss of electrons results in a positive ion or cation (pronounced cat-eye-on

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

1/7/2013. Chapter 9. Chemical Reactions in Aqueous Solutions. Chemistry: Atoms First Julia Burdge & Jason Overby. Reactions in Aqueous Solutions 9.

1/7/2013. Chapter 9. Chemical Reactions in Aqueous Solutions. Chemistry: Atoms First Julia Burdge & Jason Overby. Reactions in Aqueous Solutions 9. Chemistry: Atoms First Julia Burdge & Jason Overby 9 Reactions in Aqueous s Chapter 9 Chemical Reactions in Aqueous s Kent L. McCorkle Cosumnes River College Sacramento, CA Copyright (c) The McGraw-Hill

More information

Atomic Structure. Name Mass Charge Location Protons 1 +1 Nucleus Neutrons 1 0 Nucleus Electrons 1/1837-1 Orbit nucleus in outer shells

Atomic Structure. Name Mass Charge Location Protons 1 +1 Nucleus Neutrons 1 0 Nucleus Electrons 1/1837-1 Orbit nucleus in outer shells Atomic Structure called nucleons Name Mass Charge Location Protons 1 +1 Nucleus Neutrons 1 0 Nucleus Electrons 1/1837-1 Orbit nucleus in outer shells The number of protons equals the atomic number This

More information

SCH 4C1 Unit 2 Problem Set Questions taken from Frank Mustoe et all, "Chemistry 11", McGraw-Hill Ryerson, 2001

SCH 4C1 Unit 2 Problem Set Questions taken from Frank Mustoe et all, Chemistry 11, McGraw-Hill Ryerson, 2001 SCH 4C1 Unit 2 Problem Set Questions taken from Frank Mustoe et all, "Chemistry 11", McGraw-Hill Ryerson, 2001 1. A small pin contains 0.0178 mol of iron. How many atoms of iron are in the pin? 2. A sample

More information

Acid/base Definitions. Acid/Base Definitions. Acid / Base Chemistry. Acid/Base Definitions. Identifying Acids and Bases

Acid/base Definitions. Acid/Base Definitions. Acid / Base Chemistry. Acid/Base Definitions. Identifying Acids and Bases Acids Identifying Acids and Bases Acid (anhydrides) contains H+ ions as the cation, with and other element as the anion Non-metal oxide H2SO4 HI P2O5 Bases Base (anhydrides) Contains OH- as the anion Combined

More information

Moles. Moles. Moles. Moles. Balancing Eqns. Balancing. Balancing Eqns. Symbols Yields or Produces. Like a recipe:

Moles. Moles. Moles. Moles. Balancing Eqns. Balancing. Balancing Eqns. Symbols Yields or Produces. Like a recipe: Like a recipe: Balancing Eqns Reactants Products 2H 2 (g) + O 2 (g) 2H 2 O(l) coefficients subscripts Balancing Eqns Balancing Symbols (s) (l) (aq) (g) or Yields or Produces solid liquid (pure liquid)

More information

Writing, Balancing and Predicting Products of Chemical Reactions.

Writing, Balancing and Predicting Products of Chemical Reactions. Writing, Balancing and Predicting Products of Chemical Reactions. A chemical equation is a concise shorthand expression which represents the relative amount of reactants and products involved in a chemical

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

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

IB Chemistry. DP Chemistry Review

IB Chemistry. DP Chemistry Review DP Chemistry Review Topic 1: Quantitative chemistry 1.1 The mole concept and Avogadro s constant Assessment statement Apply the mole concept to substances. Determine the number of particles and the amount

More information

Chapter 16: Tests for ions and gases

Chapter 16: Tests for ions and gases The position of hydrogen in the reactivity series Hydrogen, although not a metal, is included in the reactivity series because it, like metals, can be displaced from aqueous solution, only this time the

More information

Physical Changes and Chemical Reactions

Physical Changes and Chemical Reactions Physical Changes and Chemical Reactions Gezahegn Chaka, Ph.D., and Sudha Madhugiri, Ph.D., Collin College Department of Chemistry Objectives Introduction To observe physical and chemical changes. To identify

More information

Department of Chemical Engineering Review Sheet Chemical Reactions Prepared by Dr. Timothy D. Placek from various sources

Department of Chemical Engineering Review Sheet Chemical Reactions Prepared by Dr. Timothy D. Placek from various sources Department of Chemical Engineering Review Sheet Chemical Reactions Prepared by Dr. Timothy D. Placek from various sources Introduction This document is intended to help you review the basics of writing

More information

Copyright 2009 by Pearson Education, Inc. Upper Saddle River, New Jersey 07458 All rights reserved.

Copyright 2009 by Pearson Education, Inc. Upper Saddle River, New Jersey 07458 All rights reserved. Sample Exercise 17.1 Calculating the ph When a Common Ion is Involved What is the ph of a solution made by adding 0.30 mol of acetic acid and 0.30 mol of sodium acetate to enough water to make 1.0 L of

More information

Chapter 16 Acid-Base Equilibria

Chapter 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 information

Topic 4 National Chemistry Summary Notes. Formulae, Equations, Balancing Equations and The Mole

Topic 4 National Chemistry Summary Notes. Formulae, Equations, Balancing Equations and The Mole Topic 4 National Chemistry Summary Notes Formulae, Equations, Balancing Equations and The Mole LI 1 The chemical formula of a covalent molecular compound tells us the number of atoms of each element present

More information

Nomenclature and Formulas of Ionic Compounds. Section I: Writing the Name from the Formula

Nomenclature and Formulas of Ionic Compounds. Section I: Writing the Name from the Formula Purpose: Theory: Nomenclature and Formulas of Ionic Compounds 1. To become familiar with the rules of chemical nomenclature, based on the classification of compounds. 2. To write the proper name of the

More information

Nomenclature of Ionic Compounds

Nomenclature of Ionic Compounds Nomenclature of Ionic Compounds Ionic compounds are composed of ions. An ion is an atom or molecule with an electrical charge. Monatomic ions are formed from single atoms that have gained or lost electrons.

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

Acid/Base Definition. Acid/Base Reactions. Major vs. Minor Species. Terms/Items you Need to Know. you need to memorize these!!

Acid/Base Definition. Acid/Base Reactions. Major vs. Minor Species. Terms/Items you Need to Know. you need to memorize these!! Acid/Base Reactions some covalent compounds have weakly bound H atoms and can lose them to water (acids) some compounds produce OH in water solutions when they dissolve (bases) acid/base reaction are very

More information

IB Chemistry 1 Mole. One atom of C-12 has a mass of 12 amu. One mole of C-12 has a mass of 12 g. Grams we can use more easily.

IB Chemistry 1 Mole. One atom of C-12 has a mass of 12 amu. One mole of C-12 has a mass of 12 g. Grams we can use more easily. The Mole Atomic mass units and atoms are not convenient units to work with. The concept of the mole was invented. This was the number of atoms of carbon-12 that were needed to make 12 g of carbon. 1 mole

More information

Practical Lesson No 4 TITRATIONS

Practical Lesson No 4 TITRATIONS Practical Lesson No 4 TITRATIONS Reagents: 1. NaOH standard solution 0.1 mol/l 2. H 2 SO 4 solution of unknown concentration 3. Phenolphthalein 4. Na 2 S 2 O 3 standard solution 0.1 mol/l 5. Starch solution

More information

Balancing Reaction Equations Oxidation State Reduction-oxidation Reactions

Balancing Reaction Equations Oxidation State Reduction-oxidation Reactions Balancing Reaction Equations Oxidation State Reduction-oxidation Reactions OCN 623 Chemical Oceanography Balanced chemical reactions are the math of chemistry They show the relationship between the reactants

More information

Question Bank Electrolysis

Question Bank Electrolysis Question Bank Electrolysis 1. (a) What do you understand by the terms (i) electrolytes (ii) non-electrolytes? (b) Arrange electrolytes and non-electrolytes from the following substances (i) sugar solution

More information

CHAPTERS 15 FAKE TEST QUESTIONS. 1. According to the Brønsted Lowry definition, which species can function both as an acid and as a base?

CHAPTERS 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 information

Chemistry Ch 15 (Solutions) Study Guide Introduction

Chemistry Ch 15 (Solutions) Study Guide Introduction Chemistry Ch 15 (Solutions) Study Guide Introduction Name: Note: a word marked (?) is a vocabulary word you should know the meaning of. A homogeneous (?) mixture, or, is a mixture in which the individual

More information

Redox and Electrochemistry

Redox and Electrochemistry Name: Thursday, May 08, 2008 Redox and Electrochemistry 1. A diagram of a chemical cell and an equation are shown below. When the switch is closed, electrons will flow from 1. the Pb(s) to the Cu(s) 2+

More information

Types of Reactions. CHM 130LL: Chemical Reactions. Introduction. General Information

Types of Reactions. CHM 130LL: Chemical Reactions. Introduction. General Information Introduction CHM 130LL: Chemical Reactions We often study chemistry to understand how and why chemicals (reactants) can be transformed into different chemicals (products) via a chemical reaction: Reactants

More information

Chapter 8 - Chemical Equations and Reactions

Chapter 8 - Chemical Equations and Reactions Chapter 8 - Chemical Equations and Reactions 8-1 Describing Chemical Reactions I. Introduction A. Reactants 1. Original substances entering into a chemical rxn B. Products 1. The resulting substances from

More information

HOMEWORK 4A. Definitions. Oxidation-Reduction Reactions. Questions

HOMEWORK 4A. Definitions. Oxidation-Reduction Reactions. Questions HOMEWORK 4A Oxidation-Reduction Reactions 1. Indicate whether a reaction will occur or not in each of following. Wtiring a balcnced equation is not necessary. (a) Magnesium metal is added to hydrochloric

More information

Chapter 12: Oxidation and Reduction.

Chapter 12: Oxidation and Reduction. 207 Oxidation- reduction (redox) reactions Chapter 12: Oxidation and Reduction. At different times, oxidation and reduction (redox) have had different, but complimentary, definitions. Compare the following

More information

CHEMISTRY 101 EXAM 3 (FORM B) DR. SIMON NORTH

CHEMISTRY 101 EXAM 3 (FORM B) DR. SIMON NORTH 1. Is H 3 O + polar or non-polar? (1 point) a) Polar b) Non-polar CHEMISTRY 101 EXAM 3 (FORM B) DR. SIMON NORTH 2. The bond strength is considerably greater in HF than in the other three hydrogen halides

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

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

ATOMS. Multiple Choice Questions

ATOMS. Multiple Choice Questions Chapter 3 ATOMS AND MOLECULES Multiple Choice Questions 1. Which of the following correctly represents 360 g of water? (i) 2 moles of H 2 0 (ii) 20 moles of water (iii) 6.022 10 23 molecules of water (iv)

More information

p3 Recognizing Acid/Base Properties when p11 Recognizing Basic versus Nonbasic

p3 Recognizing Acid/Base Properties when p11 Recognizing Basic versus Nonbasic General Chemistry II Jasperse Acid-Base Chemistry. Extra Practice Problems 1 General Types/Groups of problems: Conceptual Questions. Acids, Bases, and p1 K b and pk b, Base Strength, and using K b or p7-10

More information

Name period Unit 9: acid/base equilibrium

Name 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 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

Unit 10A Stoichiometry Notes

Unit 10A Stoichiometry Notes Unit 10A Stoichiometry Notes Stoichiometry is a big word for a process that chemist s use to calculate amounts in reactions. It makes use of the coefficient ratio set up by balanced reaction equations

More information

General Chemistry Lab Experiment 6 Types of Chemical Reaction

General Chemistry Lab Experiment 6 Types of Chemical Reaction General Chemistry Lab Experiment 6 Types of Chemical Reaction Introduction Most ordinary chemical reactions can be classified as one of five basic types. The first type of reaction occurs when two or more

More information

EXPERIMENT 8: Activity Series (Single Displacement Reactions)

EXPERIMENT 8: Activity Series (Single Displacement Reactions) EPERIMENT 8: Activity Series (Single Displacement Reactions) PURPOSE a) Reactions of metals with acids and salt solutions b) Determine the activity of metals c) Write a balanced molecular equation, complete

More information

CHAPTER 9. 9.1 Naming Ions. Chemical Names and Formulas. Naming Transition Metals. Ions of Transition Metals. Ions of Transition Metals

CHAPTER 9. 9.1 Naming Ions. Chemical Names and Formulas. Naming Transition Metals. Ions of Transition Metals. Ions of Transition Metals CHAPTER 9 Chemical Names and Formulas 9.1 Naming Ions Monatomic Ions: a single atom with a positive or negative charge Cation (rules): listed first Anion (rules): ide ending Transition Metals have a varying

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

CHEM 110: CHAPTER 3: STOICHIOMETRY: CALCULATIONS WITH CHEMICAL FORMULAS AND EQUATIONS

CHEM 110: CHAPTER 3: STOICHIOMETRY: CALCULATIONS WITH CHEMICAL FORMULAS AND EQUATIONS 1 CHEM 110: CHAPTER 3: STOICHIOMETRY: CALCULATIONS WITH CHEMICAL FORMULAS AND EQUATIONS The Chemical Equation A chemical equation concisely shows the initial (reactants) and final (products) results of

More information