Chemical Reactions CHAPTER Reactions and Equations
|
|
- Charles Short
- 6 years ago
- Views:
Transcription
1 CHAPTER 9 Chemical Reactions 9.1 Reactions and Equations The process by which atoms of one or more substances are rearranged to form different substances is called a chemical reaction. There are a number of possible indications that a chemical reaction has occurred. Among these are absorption of heat and release of energy in the form of light or heat, color change, production of an odor, and appearance of gas bubbles or a solid. Statements called equations are used to represent chemical reactions. Equations indicate the reactants, or starting substances, and the products, or substances formed during the reaction. The reactants are written to the left of an arrow that stands for yields, and the products are written to the right. Plus signs are used to separate the different reactants or products. The symbols (s), (l), (g), and (aq) indicate solid, liquid, gas, or water solution (aqueous), respectively. Equations can be in the form of word equations, in which the reactants or products are indicated by their names. Word equations can be replaced by skeleton equations, which use chemical formulas rather than words to identify reactants and products. Skeleton equations are more informative than word equations because skeleton equations identify the atoms that make up each reactant and product. Example Problem 1 Writing Word and Skeleton Equations Write a word equation and a skeleton equation for the reaction in which hydrogen gas reacts with oxygen gas to form liquid water. The word equation uses the names and physical states of the reactants and products, along with the arrow and plus symbols. hydrogen(g) oxygen(g) water(l) The skeleton equation replaces the names of the substances with their chemical formulas. H 2(g) O 2(g) H 2O(l) 81
2 1. Write a word equation and a skeleton equation for each of the following descriptions of chemical reactions. a. Solid lithium reacts with chlorine gas to produce solid lithium chloride. b. Nitrogen gas reacts with oxygen gas to produce nitrogen dioxide gas. c. Solid iron reacts with aqueous copper(ii) nitrate to produce solid copper and aqueous iron(ii) nitrate. Balanced chemical equations Skeleton equations do not reflect the fact that matter is conserved during a reaction. In actual chemical reactions, atoms are neither created nor destroyed but are conserved. An equation that reflects the fact that the same number of each kind of atom must appear on both sides of the arrow is called a balanced chemical equation. It uses chemical formulas to show the identities and relative amounts of the substances involved in a reaction. To balance a chemical equation, you write coefficients, which are numbers placed in front of the chemical formulas. The lowest wholenumber ratio is used. If no coefficient appears next to a formula, the number 1 is understood. The steps involved in balancing a chemical equation are as follows. Step 1 Write the skeleton equation. Step 2 Count the atoms of the elements in the reactants. Any polyatomic ions that remain unchanged can be counted as if they are elements. Step 3 Count the atoms of the elements in the products. Step 4 Change the coefficients to make the number of atoms of each element equal on both sides of the equation. Do not change subscripts. Step 5 Write the coefficients in their lowest possible ratio. Step 6 Check your work. 82
3 Example Problem 2 Writing a Balanced Chemical Equation Write the balanced chemical equation for the reaction in which solid sulfur (S) combines with oxygen gas to produce sulfur trioxide gas. Step 1 Write the skeleton equation. S(s) O 2(g) SO 3(g) Step 2 Count atoms of each element in the reactants. 1 S, 2 O Step 3 Count atoms of each element in the products. 1 S, 3 O Step 4 Adjust coefficients. In the formulas O 2 and SO 3, oxygen is in a 2 to 3 ratio. To balance O, 3 O 2 are needed for every 2 SO 3. Insert the coefficients 3 and 2, respectively. S(s) 3O 2(g) 2SO 3(g) Now the S atoms must be accounted for. The placement of the 2 before the SO 3 means that there are now 2 S atoms on the right. There must also be 2 on the left. Place the coefficient 2 in front of the reactant S. 2S(s) 3O 2(g) 2SO 3(g) Step 5 Write the coefficients in their lowest possible ratio. The ratio 2:3:2 cannot be written any lower and still produce whole numbers. The ratio is already the lowest possible. Step 6 Check your work. Count the number of atoms of each element on both sides of the equation and make sure they are equal. Reactants: 2 S, 6 O Products: 2 S, 6 O The numbers are equal, so the equation is correctly balanced. 83
4 2. Write a balanced chemical equation for the following reactions, making sure coefficients are in their lowest possible ratio. a. Solid potassium reacts with liquid water to produce hydrogen gas and a water solution of potassium hydroxide. b. Calcium chloride and sodium carbonate in water solution produce solid calcium carbonate and a water solution of sodium chloride. c. Liquid bromine and solid lithium iodide react to form solid lithium bromide and solid iodine. 9.2 Classifying Chemical Reactions Reactions can be classified into various types. In a synthesis reaction, two or more substances react to produce a single product. An example is the reaction between the elements potassium and bromine to form potassium bromide. 2K(s) Br 2(l) 2KBr(s) Synthesis reactions can also occur between compounds or between a compound and an element. In a combustion reaction, oxygen combines with a substance and produces light and heat. The burning of methane in oxygen is an example of a combustion reaction. CH 4(g) 2O 2(g) CO 2(g) 2H 2O(g) Certain reactions may be examples of both synthesis and combustion. An example is the burning of carbon. C(s) O 2(g) CO 2(g) A decomposition reaction is one in which a single compound breaks down into two or more elements or new compounds. An example is the breakdown of aluminum oxide into aluminum and oxygen gas. 2Al 2O 3(s) 4Al(s) 3O 2(g) 84
5 3. Identify each of the following skeleton equations as representing a synthesis reaction, a combustion reaction, both synthesis and combustion, or decomposition reaction. Balance each equation if necessary. a. N 2(g) + H 2(g) NH 3(g) b. CaCO 3(s) CaO(s) + O 2(g) c. Se(s) + O 2(g) SeO 3(g) d. C 2H 4(g) + O 2(g) CO 2(g) + H 2O(g) Replacement reactions In a single-replacement reaction, atoms of an element replace the atoms of another element in a compound. An example of such a reaction is the replacement by zinc metal of silver in silver nitrate water solution. Zn(s) + 2AgNO 3(aq) Zn(NO 3) 2(aq) + 2Ag(s) Not all metals will replace one another. Only a metal that is more reactive chemically will replace a chemically less reactive metal. The order of such reactivity is called an activity series, as shown below. Any metal in an activity series will replace the metals below it in their compounds. In a similar fashion, any elemental halogen will replace another halogen from its compounds if the second halogen lies below it in the periodic table. Thus, fluorine is more active than chlorine, which is more active than bromine, which is more active than iodine. 85
6 Example Problem 3 Using an Activity Series to Predict Single-Replacement Reactions Use the above activity series to predict the single-replacement reaction that will occur between aluminum metal and lead(ii) nitrate (Pb(NO 3) 2) in a water solution and write its balanced chemical equation. Aluminum is above lead in the activity series and therefore is more active. It will replace lead in its compounds in water solution. A singlereplacement reaction will take place to form the nitrate of aluminum, a group 13 metal. The skeleton equation is shown below. Al(s) + Pb(NO 3) 2(aq) Al(NO 3) 3(aq) + Pb(s) Adding coefficients, the balanced chemical equation is shown below. 2Al(s) + 3Pb(NO 3) 2(aq) 2Al(NO 3) 3(aq) + 3Pb(s) 4. Predict whether a single-replacement reaction will occur between the following pairs of possible reactants. If so, write a balanced chemical equation for the reaction. a. chlorine gas and aqueous potassium iodide b. magnesium metal and aqueous copper(ii) sulfate c. copper metal and iron(iii) chloride in water solution d. lead metal and aqueous silver nitrate In another type of replacement reaction, called a double-replacement reaction, there is an exchange of positive ions between two compounds, often in water solution. Often, a solid of low solubility is produced during the reaction and settles out of the solution. Such a solid is called a precipitate. An example of a double-replacement reaction that produces the precipitate lead(ii) chloride is the following. Pb(NO 3) 2(aq) + 2NaCl(aq) 2NaNO 3(aq) + PbCl 2(s) 5. Write a balanced chemical equation for each of the following double-replacement reactions. 86
7 a. A water solution of zinc bromide (ZnBr 2) and a water solution of potassium hydroxide form a water solution of potassium bromide and a precipitate of zinc hydroxide. b. A water solution of copper(ii) sulfate and a water solution of barium chloride produce a water solution of copper(ii) chloride and solid barium sulfate. c. A precipitate of iron(iii) carbonate and a water solution of sodium nitrate are formed when a water solution of iron(iii) nitrate and a water solution of sodium carbonate are mixed. 9.3 Reactions in Aqueous Solutions When a substance dissolves in water, a solution forms. A solution is a homogeneous mixture because it has a constant composition throughout. A solution contains one or more substances called solutes dissolved in the solvent. The solvent is the most plentiful substance in a solution. An aqueous solution is a solution in which the solvent is water. When dissolved to form aqueous solutions, the ions of ionic compounds separate. Some molecular compounds also produce dissolved ions in water. If hydrogen ions are produced, the substance is called an acid. For example, the gaseous molecular compound hydrogen chloride (HCl) forms H and Cl ions in aqueous solution, which is called hydrochloric acid. When aqueous solutions that contain ions are mixed, the ions may react in a double-replacement reaction. The product is typically a solid precipitate, water, or a gas. An example of a double-replacement reaction that produces a precipitate occurs when aqueous solutions of sodium chloride and silver nitrate are mixed to form a precipitate of solid silver chloride. NaCl(aq) + AgNO 3(aq) NaNO 3(aq) + AgCl(s) To show all of the particles in solution as they really exist, a complete ionic equation can be written. Na (aq) + Cl (aq) + Ag (aq) + NO 3 (aq) Na (aq) + NO 3 (aq) + AgCl(s) The sodium and nitrate ions are on both sides of the equation. Such ions that do not participate in a reaction are called spectator ions. An ionic equation that does not show spectator ions but only the particles that 87
8 participate in a reaction is called a net ionic equation. In the case of the reaction above, the net ionic equation from which the sodium and nitrate ions have been removed is as follows. Cl (aq) + Ag (aq) AgCl(s) Example Problem 4 Writing Ionic Equations Write the balanced chemical equation for the reaction between aqueous solutions of strontium nitrate and potassium sulfate, which forms the precipitate strontium sulfate. Then write the complete ionic and net ionic equations. Write the correct skeleton equation. Sr(NO 3) 2(aq) + K 2SO 4(aq) KNO 3(aq) + SrSO 4(s) Use coefficients to produce the balanced chemical equation. Sr(NO 3) 2(aq) + K 2SO 4(aq) 2KNO 3(aq) + SrSO 4(s) Write the complete ionic equation. Sr 2 (aq) + 2NO 3 (aq) + 2K (aq) + SO 4 2 (aq) 2K (aq) + 2NO 3 (aq) + SrSO 4(s) Cross out the spectator ions, which are those that are on both sides of the equation. 2 2 Sr (aq) 2NO (aq) 2K (aq) SO (aq) 3 4 That leaves the net ionic equation. Sr 2 (aq) + SO 4 2 (aq) SrSO 4(s) 2K (aq) 2NO 3 (aq) SrSO 4 (s) 6. Write balanced chemical, complete ionic, and net ionic equations for each of the following reactions. a. Aqueous solutions of lead(ii) nitrate and ammonium chloride are mixed, forming a precipitate of lead(ii) chloride. b. Aqueous solutions of aluminum chloride and sodium carbonate are combined, producing solid aluminum carbonate. 88
9 Reactions that form water or a gas Some double-replacement reactions in aqueous solution produce water or a gas (or both) rather than a precipitate. In such cases, the water or gas is shown as a product in the net ionic equation, as are the ions that produced it. The remaining ions are eliminated as spectator ions. The following example problem illustrates this concept. Example Problem 5 Writing Equations for a Reaction That Produces Water When hydrochloric acid and potassium hydroxide solutions are mixed, water results, together with an aqueous solution of potassium chloride. Write the balanced chemical equation, a complete ionic equation, and a net ionic equation for this reaction. The balanced chemical equation is the same as the skeleton equation. HCl(aq) + KOH(aq) H 2O(l) + KCl(aq) Write the complete ionic equation, which includes all of the ions. H (aq) + Cl (aq) + K (aq) + OH (aq) H 2O(l) + K (aq) + Cl (aq) Remove the spectator ions to produce the net ionic equation. H (aq) + OH (aq) H 2O(l) 7. Write balanced chemical, complete ionic, and net ionic equations for the reactions between the following substances, which produce water. a. nitric acid (HNO 3) and aqueous barium hydroxide b. sulfuric acid (H 2SO 4) and aqueous sodium hydroxide c. phosphoric acid (H 3PO 4) and aqueous lithium hydroxide Example Problem 6 Writing Equations for a Reaction That Produces a Gas Write balanced chemical, complete ionic, and net ionic equations for the reaction between aqueous solutions of sodium sulfide and hydrochloric acid. Hydrogen sulfide gas is produced, along with an aqueous solution of sodium chloride. 89
10 Write the skeleton equation with the correct formulas. Na 2S(aq) + HCl(aq) NaCl(aq) + H 2S(g) Add coefficients to write a balanced chemical equation. Na 2S(aq) + 2HCl(aq) 2NaCl(aq) + H 2S(g) Write the complete ionic equation, which includes all the ions. 2Na (aq) + S 2 (aq) + 2H (aq) + 2Cl (aq) 2Na (aq) + 2Cl (aq) + H 2S(g) Remove the spectator ions to produce the net ionic equation. S 2 (aq) + 2H (aq) H 2S(g) 8. Write balanced chemical, complete ionic, and net ionic equations for the reactions between the following substances, which produce a gas. a. hydrochloric acid and aqueous sodium cyanide, with production of hydrogen cyanide gas (HCN) b. sulfuric acid (H 2SO 4) and aqueous rubidium sulfide, with production of hydrogen sulfide gas Chapter 9 Review 9. Define chemical reaction. Where are the reactants and products shown in an equation for a chemical reaction, and how are the physical states indicated? 10. Compare and contrast word equations, skeleton equations, and balanced chemical equations. 11. Briefly list the steps used in balancing a chemical equation. 12. Contrast synthesis, combustion, and decomposition reactions. 13. Contrast single-replacement and double-replacement reactions. 14. Define aqueous solution. What name is given to a solid that forms when two aqueous solutions are mixed? 15. How do complete ionic and net ionic equations differ? 16. Name three typical types of products that may be formed in doublereplacement reactions. 90
11.2 Types of Chemical Reactions> Chapter 11 Chemical Reactions Types of Chemical Reactions Describing Chemical Reactions
Chapter 11 Chemical 11.1 Describing Chemical 11.2 Types of Chemical 11.3 in Aqueous Solution 1 CHEMISTRY & YOU What happens to the wax when you burn a candle? When you burn a candle, a chemical reaction
More informationIntro to Reactions/ Balancing Equations
Intro to Reactions/ Balancing Equations Chemical Reactions Chemical reactions involve change. Evidence of a chemical reaction could include the following Evolution of heat, light, and/or sound Production
More informationChapter 8 Chemical Reactions
Chemistry/ PEP Name: Date: Chapter 8 Chemical Reactions Chapter 8: 1 7, 9 18, 20, 21, 24 26, 29 31, 46, 55, 69 Practice Problems 1. Write a skeleton equation for each chemical reaction. Include the appropriate
More informationChemical Reactions. Ch. 11 Chemical Reactions. Chemical Reactions. Chemical Reactions
Chemical Reactions Ch. 11 Chemical Reactions when a substance changes identity Reactants - original Products - resulting law of conservation of mass total mass of reactants = total mass of products In
More informationName Date Class STUDY GUIDE FOR CONTENT MASTERY
Chemical Reactions Section 10.1 Reactions and Equations In your textbook, read about evidence of chemical reactions. For each statement, write yes if evidence of a chemical reaction is present. Write no
More informationFe(s) + O2(g) Chapter 11 Chemical Reactions. Chemical Equations. Fe + O2. January 26, What is a chemical reaction?
Chapter 11 Chemical Reactions What is a chemical reaction? Chemical Reaction: process by which one or more substances are changed into one or more different substances. Indications of a chemical reaction
More informationChemical Reactions and Equations
Chemical Reactions and Equations 5-1 5.1 What is a Chemical Reaction? A chemical reaction is a chemical change. A chemical reaction occurs when one or more substances is converted into one or more new
More informationChapter 6. Chemical Reactions. Sodium reacts violently with bromine to form sodium bromide.
Chapter 6 Chemical Reactions Sodium reacts violently with bromine to form sodium bromide. Evidence of Chemical Reactions Chemical Equations Reactants Products Reactant(s): Substance(s) present before the
More informationName HONORS CHEMISTRY / / Oxide Reactions & Net Ionic Reactions
Name HONORS CHEMISTRY / / Oxide Reactions & Net Ionic Reactions The first type of reactions we will look at today are reactions between an oxide (a compound with oxygen as its anion) and water. There are
More informationChemical Equations and Chemical Reactions
Chemical Equations Chemical Equations and Chemical Reactions Chemical equations are concise representations of chemical reactions. Chemical Equations Symbols Used in Chemical Equations The formulas of
More informationName CHEMISTRY / / Oxide Reactions & Net Ionic Reactions
Name CHEMISTRY / / Oxide Reactions & Net Ionic Reactions The first type of reactions we will look at today are reactions between an oxide (a compound with oxygen as its anion) and water. There are two
More informationBalancing Equations Notes
. Unit 9 Chemical Equations and Reactions What is a Chemical Equation? A is a written representation of the process that occurs in a chemical reaction. A chemical equation is written with the (starting
More informationDefinition: the process by which one or more substances are rearranged to form different substances. Another name for a chemical change.
Chemical Reactions I. What is a chemical reaction? Definition: the process by which one or more substances are rearranged to form different substances. Another name for a chemical change. A. How can you
More informationName Date Class CHEMICAL REACTIONS. SECTION 11.1 DESCRIBING CHEMICAL REACTIONS (pages )
Name Date Class 11 CHEMICAL REACTIONS SECTION 11.1 DESCRIBING CHEMICAL REACTIONS (pages 321 329) This section explains how to write equations describing chemical reactions using appropriate symbols. It
More informationChemical Reactions. Chemical changes are occurring around us all the time
Chemical changes are occurring around us all the time Food cooking Fuel being burned in a car s engine Oxygen being used in the human body The starting materials are called reactants The ending materials
More informationIdentify the reaction type, predict the products, and balance the equations. If it is a special decomposition or synthesis, identify which kind.
Identify the reaction type, predict the products, and balance the equations. If it is a special decomposition or synthesis, identify which kind. 1. calcium + oxygen 2. cupric carbonate 3. aluminum + hydrochloric
More informationCh. 8 Chemical Reactions
Ch. 8 Chemical Reactions Intro to Reactions I II III IV V Signs of a Chemical Reaction Evolution of heat and light Formation of a gas Formation of a precipitate Color change Law of Conservation of Mass
More informationDescribing Chemical Reactions
Describing Chemical Reactions Section 11.1-Describing Chemical Reactions To write a word equation, write the names of the reactants to the left of the arrow separated by plus signs; write the names of
More informationCHEMICAL REACTIONS. The process by which one or more substances are changed into one or more different substances
CHEMICAL REACTIONS The process by which one or more substances are changed into one or more different substances Equations Reactions are represented by a chemical equation Reactants Products Must have
More informationBalancing Equations Notes
. Unit 7 Chemical Equations and Reactions What is a Chemical Equation? A is a written representation of the process that occurs in a chemical reaction. A chemical equation is written with the (starting
More informationPart 01 - Notes: Reactions & Classification
Objectives: Identify, define, and explain: combination reaction, synthesis reaction, decomposition reaction, single replacement reaction, double replacement reaction, combustion reaction, rapid oxidation,
More informationStudy Guide: Stoichiometry
Name: Study Guide: Stoichiometry Period: **YOUR ANSWERS MUST INCLUDE THE PROPER NUMBER OF SIG FIGS AND COMPLETE UNITS IN ORDER TO RECEIVE CREDIT FOR THE PROBLEM.** BALANCE THE FOLLOWING EQUATIONS TO USE
More informationBalancing Equations Notes
. Unit 9 Chemical Equations and Reactions What is a Chemical Equation? A Chemical Equation is a written representation of the process that occurs in a chemical reaction. A chemical equation is written
More informationUnit 8 Chemical Reactions- Funsheets
Part A- Balancing Equations and Types of Reactions Balance AND identify the following reactions: Unit 8 Chemical Reactions- Funsheets 1) Mg + Zn(NO 3) 2 Zn Mg(NO 3) 2 2) Ba + AgNO 3 Ag + Ba(NO 3) 2 3)
More informationCh 7 Chemical Reactions Study Guide Accelerated Chemistry SCANTRON
Ch 7 Chemical Reactions Study Guide Accelerated Chemistry SCANTRON Name /80 TRUE/FALSE. Write 'T' if the statement is true and 'F' if the statement is false. Correct the False statments by changing the
More informationChemical Reactions. Section 9.1 Reactions and Equations
9 Chemical Reactions Section 9.1 Reactions and Equations In your textbook, read about evidence of chemical reactions. For each statement, write yes if evidence of a chemical reaction is present. Write
More informationChapter 9. Vocabulary Ch Kick Off Activity. Objectives. Interpreting Formulas. Interpreting Formulas
Chapter 9 Chemical Vocabulary Ch. 9.1 Chemical reaction Reactant Product Word Equation Skeleton Equation Chemical equation Coefficient 1 2 Objectives Write chemical equations to describe chemical reactions
More informationSolubility Rules and Net Ionic Equations
Solubility Rules and Net Ionic Equations Why? Solubility of a salt depends upon the type of ions in the salt. Some salts are soluble in water and others are not. When two soluble salts are mixed together
More informationCHAPTER Describing Chemical Reactions Reactants Products. New substances produced The arrow means yields TYPES OF EQUATIONS.
CHAPTER 11 Chemical Reactions 11.1 Describing Chemical Reactions Reactants Products New substances produced The arrow means yields Where do Chemical Reactions occur? Everywhere!!! In living organisms In
More informationBalancing Equations Notes
. Unit 6 Chemical Equations and Reactions What is a Chemical Equation? A Chemical Equation is a written representation of the process that occurs in a chemical reaction. A chemical equation is written
More informationHonors Chemistry - Unit 7 Chapter 11 Chemical Reactions
Honors Chemistry - Unit 7 Chapter 11 Chemical Reactions Important Dates: Diatomics, Reaction Symbols, Balancing Quiz: January 4 th Unit 7 UT Quest (2 parts): Due11:58pm on January 8 th Unit 7 Packet -
More informationChemical Reactions. Chemical Reactions Chemical reactions have a standard format when written:
0.3.notebook A chemical property is a behaviour that occurs when substances change to create a new substance. When a new substance is created, a chemical change has occurred. New colour Evidence of chemical
More informationReaction Writing Sheet #1 Key
Reaction Writing Sheet #1 Key Write and balance each of the following reactions and indicate the reaction type(s) present: 1. zinc + sulfur zinc sulfide 8 Zn (s) + S 8 (s) 8 ZnS (s) synthesis 2. potassium
More informationTopic 8: Chemical Reactions Chemical Equations & Reactions
Topic 8: Chemical Reactions Chemical Equations & Reactions (Chapter 8 in Modern Chemistry) Describing Chemical Reactions A chemical reaction is the process by which one or more substances are changed into
More informationCHAPTER 11: CHEMICAL REACTIONS. Mrs. Brayfield
CHAPTER 11: CHEMICAL REACTIONS Mrs. Brayfield WRITING EQUATIONS Write the chemical equation for the following: Magnesium metal reacts with hydrochloric acid to form aqueous magnesium chloride and hydrogen
More informationThe photograph in the textbook provides evidence that an exothermic chemical reaction is occurring.
Preview Lesson Starter Objectives Indications of a Chemical Reaction Characteristics of Chemical Equations Significance of a Chemical Equation Balancing Chemical Equations Section 1 Describing Chemical
More informationName Date Class CHEMICAL REACTIONS. SECTION 11.1 DESCRIBING CHEMICAL REACTIONS (pages )
Name Date Class 11 CHEMICAL REACTIONS SECTION 11.1 DESCRIBING CHEMICAL REACTIONS (pages 321 329) This section explains how to write equations describing chemical reactions using appropriate symbols. It
More information9-1 The Nature of Chemical Reactions
9-1 The Nature of Chemical Reactions What are chemical reactions and why do they occur? A chemical reaction is a process in which one or more substances are converted into new substances with different
More informationBALANCING EQUATIONS NOTES
BALANCING EQUATIONS NOTES WHY DO WE NEED TO BALANCE CHEMICAL EQUATIONS? The LAW OF CONSERVATION OF MASS says that matter cannot be created or destroyed. In other words, you cannot end up with any more
More informationCHAPTER 8 CHEMICAL REACTIONS AND EQUATIONS
CHAPTER 8 CHEMICAL REACTIONS AND EQUATIONS CHEMICAL REACTIONS Occurs when matter combines or breaks apart to produce new kinds of matter with different properties with a change in energy. EVIDENCE FOR
More informationCHEMICAL REACTIONS. Introduction. Chemical Equations
CHEMICAL REACTIONS Chemistry I Chapter 7 1 Chemical Equations Their Job: Depict the kind of reactants and products and their relative amounts in a reaction. 4 Al (s) + 3 O 2 (g) ---> 2 Al 2 O 3 (s) The
More informationCHEMICAL EQUATIONS WHAT BALANCING AN EQUATION MEANS
17 CHEMICAL EQUATIONS WHAT BALANCING AN EQUATION MEANS WHAT IS A CHEMICAL EQUATION? A chemical equation is a way of representing a chemical reaction in symbolic form. For example, when hydrochloric acid
More informationChapter 9. Chemical Reaction
Chapter 9 Chemical Reaction Everyday Chemical Reaction O Can you name some? O Cooking Pizza O Changes the ingredients O Combustion O Driving to school burns gasoline O Wheelbarrow rusting (especially in
More informationChemical reactions describe processes involving chemical change
1.1 Chemical Reactions 1.2 Chemical Equations Chemical reactions describe processes involving chemical change The chemical change involves rearranging matter Converting one or more pure substances into
More informationChem A Ch. 9 Practice Test
Name: Class: Date: Chem A Ch. 9 Practice Test Matching Match each item with the correct statement below. a. product d. balanced equation b. reactant e. skeleton equation c. chemical equation 1. a new substance
More informationChapter 5 Classification and Balancing of Chemical Reactions
Chapter 5 Classification and Balancing of Chemical Reactions 5.1 Chemical Equations Chemical equations describe chemical reactions. - As words: hydrogen plus oxygen combine to form water - As a chemical
More information11.3 Reactions in Aqueous Solution. Chapter 11 Chemical Reactions Reactions in Aqueous Solution
Chapter 11 Chemical Reactions 11.1 Describing Chemical Reactions 11.2 Types of Chemical Reactions 11.3 Reactions in Aqueous Solution 1 CHEMISTRY & YOU How did soda straws get into limestone caves? These
More informationCHEMISTRY 135 REVISION OF NAMES, FORMULAE AND EQUATIONS
CHEMISTRY 135 REVISION OF NAMES, FORMULAE AND EQUATIONS Answer the following questions as if you were going to hand them in for marking. You will be tested on them in class time. 1) Give the correct chemical
More informationHonors Chemistry - Unit 7 Chapter 11 Chemical Reactions
Honors Chemistry - Unit 7 Chapter 11 Chemical Reactions Vocab Assignment Due: Unit 7 Packet - Page 1 of 15 UT Quest(s): Quiz on Diatomic Molecules & Balancing: Prediction Quiz : Test Date: VOCABULARY Assignment
More information11-1 Notes. Chemical Reactions
11-1 Notes Chemical Reactions Chemical Reactions In a chemical reaction 1 or more substances (the reactants) change into 1 or more new substances (the products). Reactants are always written on the left
More information2) Solve for protons neutrons and electrons for the bromide ION.
1) Write the formulas for the following a) Calcium nitride c)lithium hydroxide b) Iron (III) sulfide d) sulfuric acid 2) Solve for protons neutrons and electrons for the bromide ION. 3) Write the electron
More informationDescribing Chemical Reactions
Describing Chemical Reactions Key Terms chemical equation precipitate coefficient word equation formula equation reversible reaction A chemical reaction is the process by which one or more substances are
More informationAqueous Reactions. The products are just the cation-anion pairs reversed, or the outies (A and Y joined) and the innies (B and X joined).
Aqueous Reactions Defining Aqueous Reactions Aqueous reactions are reactions that take place in water. To understand them, it is important to understand how compounds behave in water. Some compounds are
More information26. N 2 + H 2 NH N 2 + O 2 N 2 O 28. CO 2 + H 2 O C 6 H 12 O 6 + O SiCl 4 + H 2 O H 4 SiO 4 + HCl 30. H 3 PO 4 H 4 P 2 O 7 + H 2 O
Balance the following chemical equations: (Some may already be balanced.) 1. H 2 + O 2 H 2 O 2. S 8 + O 2 SO 3 3. HgO Hg + O 2 4. Zn + HCl ZnCl 2 + H 2 5. Na + H 2 O NaOH + H 2 6. C 10 H 16 + Cl 2 C +
More informationWhat is one of the spectator ions (with correct coefficient)? A)
Chem 101 Exam Fall 01 Section 001 1. Based on the solubility rules Mg (PO 4 ) is A) soluble B) insoluble. An aqueous solution of potassium sulfate is allowed to react with an aqueous solution of What is
More informationUnit 1 - Foundations of Chemistry
Unit 1 - Foundations of Chemistry Chapter 2 - Chemical Reactions Unit 1 - Foundations of Chemistry 1 / 42 2.1 - Chemical Equations Physical and Chemical Changes Physical change: A substance changes its
More informationIntroduction to Chemical Equations. Introduction to Chemical Equations. How do you write a skeleton equation?
Introduction to Chemical Equations Introduction to Chemical Equations How do you write a skeleton equation? Introduction to Chemical Equations All chemical reactions involve changing substances. In a chemical
More information11.3 Reactions in Aqueous Essential Understanding Reactions that occur in aqueous solutions are double-replacement
13. Is the following sentence true or false? Hydrocarbons, compounds of hydrogen and carbon, are often the reactants in combustion reactions. 14. Circle the letter of each compound that can be produced
More informationMultiple Choice Identify the letter of the choice that best completes the statement or answers the question.
Chapter 8 Prep Test Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. General Solubility Guidelines 1. Most sodium, potassium, and ammonium compounds
More informationChemical Reactions Worksheets
Germanium 32 Ge 72.61 Nickel 28 Ni 8.693 Uranium 92 U 238.029 Sulfur 16 S 32.066 Worksheets Reactions and Equations Chemical reactions take place when the bonds between atoms are broken and new bonds are
More informationChapter 5. Chemical reactions
Chapter 5 Chemical reactions Chemical equations CaO(s) + CO 2 (g) CaCO 3 (s) + CO(g) Chemical equation - representation of a chemical reaction; uses the symbols of the elements and formulae of the compounds
More informationCheck Your Solution The net ionic equation is balanced, including the charges on the ions.
Ba 2+ (aq) + 2PO (aq) Ba (PO ) 2 (s) 2. Practice Problem (page 10) Write the net ionic equation for this reaction: Na 2 SO (aq) + Sr(OH) 2 (aq) SrSO (s) + NaOH(aq) You need to write the net ionic equation
More informationNotes: Chemical Reactions. Diatomic elements: H 2, N 2, O 2, F 2, Cl 2, Br 2, I 2 I Bring Clay For Our New Hut OR HOBrFINCl
Name Chemistry-PreAP Notes: Chemical Reactions Period Review: Some elements do not occur as single atoms when uncombined with other elements. They will bond with themselves, forming a molecule. In any
More informationNET IONIC REACTIONS in AQUEOUS SOLUTIONS AB + CD AD + CB
NET IONIC REACTIONS in AQUEOUS SOLUTIONS Double replacements are among the most common of the simple chemical reactions. Consider the hypothetical reaction: AB + CD AD + CB where AB exists as A + and B
More informationUnit 4: Reactions and Stoichiometry
Unit 4: Reactions and Stoichiometry Reactions Chemical equation Expression representing a chemical reaction Formulas of reactants on the left side Formulas of products on the right side Arrow(s) connect(s)
More informationNet Ionic Equations. Making Sense of Chemical Reactions
Making Sense of Chemical Reactions Now that you have mastered writing balanced chemical equations it is time to take a deeper look at what is really taking place chemically in each reaction. There are
More informationinsoluble partial very soluble (< 0.1 g/100ml) solubility (> 1 g/100ml) Factors Affecting Solubility in Water
Aqueous Solutions Solubility is a relative term since all solutes will have some solubility in water. Insoluble substances simply have extremely low solubility. The solubility rules are a general set of
More informationBalancing CHEMICAL EQUATIONS
Balancing CHEMICAL EQUATIONS CHEMICAL REACTIONS involves a chemical change in the identity of one or more chemical species Ex. Rusting of iron (Fe): chemical rxn btwn water and iron involve the breaking
More informationReactions in Aqueous Solutions
Reactions in Aqueous Solutions 1 Chapter 4 General Properties of Aqueous Solutions (4.1) Precipitation Reactions (4.2) Acid-Base Reactions (4.3) Oxidation-Reduction Reactions (4.4) Concentration of Solutions
More informationCH 221 Chapter Four Part II Concept Guide
CH 221 Chapter Four Part II Concept Guide 1. Solubility Why are some compounds soluble and others insoluble? In solid potassium permanganate, KMnO 4, the potassium ions, which have a charge of +1, are
More informationChapter 4 Electrolytes and Aqueous Reactions. Dr. Sapna Gupta
Chapter 4 Electrolytes and Aqueous Reactions Dr. Sapna Gupta Aqueous Solutions Solution - a homogeneous mixture of solute + solvent Solute: the component that is dissolved Solvent: the component that does
More information(DO NOT WRITE ON THIS TEST)
Final Prep Chap 8&9 (DO NOT WRITE ON THIS TEST) Multiple Choice Identify the choice that best completes the statement or answers the question. 1. After the correct formula for a reactant in an equation
More informationChemical Reaction Types
Chemical Reactions Chemical Reaction Types There are 5 types of chemical reactions that you need to know Combination reaction Decomposition reaction Combustion reaction Single replacement (redox) reaction
More informationUnit Two Worksheet WS DC U2
Unit Two Worksheet WS DC U2 Name Period Short Answer [Writing]. Write skeleton equations representing the following reactions and then balance them. Then identify the reaction type. Include all needed
More informationWhich of the following answers is correct and has the correct number of significant figures?
Avogadro s Number, N A = 6.022 10 23 1. [7 points] Carry out the following mathematical operation: 6.06 10 3 + 1.1 10 2 Which of the following answers is correct and has the correct number of significant
More informationCHEMISTRY 20 Simple Composition (Formation) and Simple Decomposition Reactions! (sc aka f) elements combine to form one single product! (sd) reactant breaks down to form pure elements from the periodic
More informationChapter 8 Chemical Equations and Reactions
Chapter 8 Chemical Equations and Reactions 8-1 Describing Chemical Reactions Chemical reactions Matter undergoes 2 types of changes: 1.Physical changes no new substance produced 2.Chemical changes new/different
More informationChemical Reactions Chapter 11 Study Guide (Unit 8)
Name: Hr: Understand and be able to explain all of the key concepts. Define and understand all of the survival words Memorize the names and symbols for these elements: (Ag, Al, Ar, As, Au, B, Ba, Be, Br,
More informationTypes of Reactions: Reactions
1 Reactions On the A.P. Test there will be one question (question #4) that will say: Give the formulas to show the reactants and the products for the following chemical reactions. Each occurs in aqueous
More informationTypes of Chemical Reactions
Types of Chemical Reactions 1) Combination (Synthesis) Reaction 2) Decomposition 3) Single Replacement 4) Double Replacement 5) Combustion 6) Oxidation-Reduction (Redox) Combination (Synthesis) Reactions
More informationTypes of Chemical Reactions
Types of Chemical Reactions There are five types of chemical reactions: 1. Formation (combination) 2. Decomposition 3. Single Displacement 4. Double Displacement 5. Combustion 1 Formation (Combination)
More informationChapter 04. Reactions in Aqueous Solution
Chapter 04 Reactions in Aqueous Solution Composition Matter Homogeneous mixture Contains One visible distinct phase Uniform properties throughout Two or more substances that are mixed together Substances
More informationIndicators of chemical reactions
Indicators of chemical reactions Emission of light or heat Formation of a gas Formation of a precipitate Color change Emission of odor All chemical reactions: have two parts Reactants - the substances
More informationHonors text: Ch 10 & 12 Unit 06 Notes: Balancing Chemical Equations
Notes: Balancing Chemical Equations Effects of chemical reactions: Chemical reactions rearrange atoms in the reactants to form new products. The identities and properties of the products are completely
More informationChem!stry. Assignment on Acids, Bases and Salts #
Chem!stry Name: ( ) Class: Date: / / Assignment on Acids, Bases and Salts #5 Write your answers in the spaces below: 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. 1. Which of the
More informationTypes of Reactions: Reactions
1 Reactions On the A.P. Test there will be one question (question #4) that will say: Give the formulas to show the reactants and the products for the following chemical reactions. Each occurs in aqueous
More informationChemical Bonds In elements and compounds, the atoms are held together by chemical bonds.
Chemical Bonds In elements and compounds, the atoms are held together by chemical bonds. Forming a bond makes an atom more stable, so atoms form as many bonds are they are able to. Bonds are made using
More informationReactions in Aqueous Solutions
Copyright 2004 by houghton Mifflin Company. Reactions in Aqueous Solutions Chapter 7 All rights reserved. 1 7.1 Predicting if a Rxn Will Occur When chemicals are mixed and one of these driving forces can
More informationVOCABULARY Define. 1. reactants. 2. products. 3. chemical equation. 4. precipitate. 5. word equation
CHAPTER 8 HOMEWORK 8-1 (pp. 241 245) Define. 1. reactants 2. products 3. chemical equation 4. precipitate 5. word equation GRAPHIC ORGANIZER Complete the chart by listing three signs that suggest that
More informationChemical Reactions. Section 9.1 Reactions and Equations Section 9.2 Classifying Chemical Reactions Section 9.3 Reactions in Aqueous Solutions
Chemical Reactions Section 9.1 Reactions and Equations Section 9.2 Classifying Chemical Reactions Section 9.3 Reactions in Aqueous Solutions Click a hyperlink or folder tab to view the corresponding slides.
More informationChapter 7 Chemical Reactions
Chapter 7 Chemical Reactions Evidence of Chemical Change Release or Absorption of Heat Color Change Emission of Light Formation of a Gas Formation of Solid Precipitate Tro's "Introductory 2 How Do We Represent
More informationChapter 3 & 4: Reactions Part 1
Chapter 3 & 4: Reactions Part 1 Read: BLB 3.1 3.2; 4.2 4.4 HW: BLB 3:1, 11a, b, e, 13 4:19, 24, 39, 49a, c, e, f, 51b, d Supplemental: Rxns:1, 2, 6 11 Know: Chapter 3 Reactions Combustion Decomposition
More informationWhat Do You Think? Investigate GOALS
Cool Chemistry Show Activity 4 Chemical Equations GOALS In this activity you will: Represent chemical changes using word equations and chemical equations. Distinguish between different classes of chemical
More informationClassifying Chemical Reactions
1 Classifying Chemical Reactions Analyzing and Predicting Products Introduction The power of chemical reactions to transform our lives is visible all around us-in our cars, even in our bodies. Chemists
More informationChapter 8. Chemical Equations and Reactions
Chapter 8 Chemical Equations and Reactions Chemical Equations Represents, w/ symbols & formulas, the reactants & products in a chemical reaction Requirements Must represent the known facts Must contain
More information2. Indicators of Chemical Rxns. Abbreviations of State (g) gas (l) liquid (s) solid (aq) aqueous a substance dissolved in water
Unit 6 Chemical Reactions 1. Parts of a Chemical Reaction 2. Indicators of a Chemical Reaction 3. Enthalpy 4. Balancing Chemical Equations 5. Word Equations 6. Classifying Chemical Reactions 7. Predicting
More informationCHAPTER 7 CHEMICAL REACTIONS: AN INTRODUCTION
Chemistry Name Hour Chemistry Approximate Timeline Students are expected to keep up with class work when absent. CHAPTER 7 CHEMICAL REACTIONS: AN INTRODUCTION Day Plans for the day Assignment(s) for the
More informationName Honors Chemistry / / Chemical Equations Reactions
Name Honors Chemistry / / Chemical Equations Reactions Like everything else in chemistry, chemical equations follow a few basic patterns. Today we will begin to look at the first of these patterns and
More informationSlide 1 / 90. Stoichiometry HW. Grade:«grade» Subject: Date:«date»
Slide 1 / 90 Stoichiometry HW Grade:«grade» Subject: Date:«date» Slide 2 / 90 1 The calculation of quantities in chemical equations is called. A B C D E accuracy and precision dimensional analysis percent
More informationReaction Types and Chemical Equations
Cool Chemistry Show Section 4 Reaction Types and Chemical Equations What Do You See? Learning Outcomes In this section you will Represent chemical changes using word equations and chemical equations. Distinguish
More information