As well, we added stick-Like drawings to show the shapes of molecules--drawings that students can mimic- along with artistic three-dimensional renderings that students will not be able to reproduce easily. Worked examples are one of the most important and wellused features in this textbook.
To continue this strength, we have added some new worked examples, for example on reaction mechanisms in Chapter Finally, we reorganized Chapter 17 slightly by moving the discussion of the third Law of thermodynamics earlier in the chapter with the rest of the quantitative discussion of entropy.
We also introduced a new section, including worked examples, on making nonspontaneous processes spontaneous by coupling with exergonic reactions. Our second goal was to update and "evergreen" the book. To do this, we replaced or updated "Chemistry in Your Day" boxes to make them more interesting and relevant to students and thereby enhance learning. Dietmar Kennepohl Athabasca University and Dr. Nicole Sandblom University of Calgary , Dr.
Neil Anderson Onyx Pharmaceuticals , Dr. Nicholas Ryan Memorial University , and Drs. Ian Hunt of the University of Calgary worked with us in the early development of the organic chemistry chapters. He provided sage advice on the organization of these chapters and made numerous suggestions on how to present organic chemistry in a way that is both rigorous and accessible to the first-year student.
Professor Franitois Caron of Laurentian University provided expert advice on revisions to Chapter 19, improving the presentation of nuclear reaction energetics so that it is consistent with the field of nuclear chemistry.
PREFACE We would like to thank our wives, Lisa and Tanya, for their encouragement and their continuing patience during all the evenings and weekends we spent working on this book when we could have been with our families. Travis D. Fridgen Lawton E. Shaw C hemistry is relevant to every process occurring around you, at every second.
The authors help you understand this connection by weaving specific, vivid examples throughout the text that tell the story of chemistry. Every chapter begins with a brief story that illustrates how chemistry is relevant to all people, at every moment. Chapter 4 illustrates the role chemistry plays in cuisine, from baking a cake to why lemons go well with fish.
Pa11enlS suffering from os1eoporosis. Treatments for osteoporosis include add1t! Oflal cak1um and 'Ila. Question Suppose yoo find a large amnul bone 1n the v. How might OU :ippnmmatc 11s dcnsil? Wood frogs Ram1 syfw11ica look like most other frogs. They arc a few inches long and have characteristic greenish. Within 1- 2 hours of tha.
How docs the wood frog do this? When 1hc temperature drop5 below freezing. In other words. It protects tion wi1hin the frog'scells acts as antifrca. Chemistry in the Environment boxes relate chapter topics to current environmental and societal issues. The wood frog can survhe at body temperatures as low as Calculnte the mola1ity int of water to - 8. By the end of the meal. If you try to wash them wi1h only water, the ' remain greas '. As we just learned.
As a result. One end of a soap molecule is polar. Question Consider the dc1ergcnt molecule at right. Which end do you think is polar?
Wh ich end is nonpolar? After all, this is what chemistry is all about. In an acid-base reaction also called a neutralization reaction , an acid reacts with a base and the two neutralize each other, producing water or in some cases, a weak electrolyte. As in precipitation reactions, an acid-base reaction occurs when the anion from one reactant combines with the cation of the other. Our stomachs contain hydrochloric acid, which acts in the digestion of food.
Certain foods or stress, however, can increase the stomach's acidity to uncomfortable levels, causing what has come to be known as heartburn.
Antacids are over-the-counter medicines that work by reacting with and neutralizing stomach acid. Antacids employ different bases-substances that produce hydroxide ions OH- in water-as neutralizing agents.
All antacids, regardless of the base they employ, have the same effect of neutralizing stomach acid and relieving heartburn through acid-base reactions. In Chapter 15, we will learn more general definitions of acids and bases, but these are sufficient to describe neutralization reactions. The chemical equation for the ionization of HCl is often written to show the association of the proton with a water molecule to form the hydronium ion: Some acids- called polyprotic acids-contain more than one ionizable proton and release them sequentially.
For example, sulfuric acid, H2S0 4, is a diprotic acid. Lemons, limes, and vinegar contain acids. Vitamin C and aspirin are acids. For this reason they are considered strong bases. You can find acids and bases in many everyday substances. Foods such as citrus fruits and vinegar contain acids. Soap, baking soda, and milk of magnesia all contain bases. N aOH aq Acid-base reactions generally form water and an ionic compound-called a salt-that usually remains dissolved in the solution.
Begin by writing the skeletal reaction in which the acid and the base combine to form water and a salt. Hl aq Next, balance the equation: this is the molecular equation. Acid-Base Reactions Evolving a Gas In some acid-base reactions, two aqueous solutions mix to form a gaseous product that bubbles out of solution. These reactions are sometimes called gas-evolution reactions. Some gas-evolution reactions form a gaseous product directly when the cation of one reactant combines with the anion of the other.
For example, when sulfuric acid reacts with lithium sulfide, dihydrogen sulfide gas is formed: Similarly, when acids composed of ammonium cation react in an acid- base reaction in aqueous solution, ammonia gas is evolved: Other gas-evolution reactions often form an intermediate product that then decomposes breaks down into simpler substances to form a gas.
For example, when aqueous hydrochloric acid is mixed with aqueous sodium bicarbonate, the following reactions occur: intermediate The intermediate product, H2 C0 3, is not stable and decomposes into H 20 and gaseous C0 2. TABLE 4. Begin by writing a skeletal equation in which the cation of each reactant combines with the anion of the other. You must then recognize that H2 C03 aq decomposes into H 20 l and C0 2 g , and write these products into the equation.
Finally, balance the equation. The rusting of iron , the bleaching of hair, and the production of electricity in batteries involve redox reactions. Many redox reactions for example, combustion reactions involve the reaction of a substance with oxygen Figure 4. Sodium is oxidized and chlorine is reduced. In this redox reaction, sodium is oxidized and chlorine is reduced.
We cover electronegativity in more detail in Section 9. However, redox reactions need not involve oxygen. Consider, for example, the reaction between sodium and chlorine to form sodium chloride NaCl , depicted in Figure 4. In both cases, metal atoms lose electrons to nonmetal atoms. A fundamental defin ition of oxidation is the loss of electrons, and a fundamental definition of reduction is the gain of electrons.
The transfer of electrons need not be a complete transfer as occurs in the formation of an ionic compound for the reaction to qualify as oxidation-reduction. Even though hydrogen chloride is a molecular compound with a covalent bond, and even though the hydrogen has not completely transferred its electron to chlorine during the reaction, you can see from the electron density diagrams Figure 4. In the reaction, hydrogen is oxidized and chlorine is reduced and, therefore, this is a redox reaction.
Identifying whether or not a reaction between a metal and a nonmetal is a redox reaction is fairly straightforward because of ion formation. But how do we identify redox reactions that occur between nonmetals? Chemists have devised a scheme to track electrons before and after a chemical reaction. In this scheme- which is like bookkeeping for electronseach shared electron is assigned to the atom that attracts the electrons most strongly. Oxidation States 4. In other words, the oxidation number of an atom in a compound is the "charge" it would have if all shared electrons were assigned to the atom with the greatest attraction for those electrons.
For example, consider HCI. You can use the following rules to assign oxidation states to atoms in elements and compounds. Oxidation-Reduction Reactions Do not confuse oxidation state with ionic charge. Unlike ionic charge- which is a real property of an ion- the oxidation state of an atom is merely a theoretical but useful construct.
Rules for Assigning Oxidation States These rules are hierarchical. If any two rules conflict, follow the rule with the smaller number i. The oxidation state of each atom in an element is 0.
The oxidation state of the atom in a monoatomic ion is equal to the ion's charge. Another point to keep in mind is that when assigning oxidation states to elements that are not covered by the rules , such as carbon, use rule 3 to deduce their oxidation state once all other oxidation states have been assigned.
According to rule 3, the sum of all oxidation states for methane must be 0, so the oxidation state of carbon must be Cl2 CIC! Since there are only two atoms in this compound, we can use rule 3 to assign an oxidation number to F. The sum of the oxidation numbers must be 0, so the oxidation number of F is - 1, which agrees with rule 6. We might expect the oxidation state of sulfur to be However, if that were the case, the sum of the oxidation states would not equal the charge on the ion.
Since 0 is mentioned higher on the list of rules than S, it takes priority and we compute the oxidation state of sulfur by setting the sum of all the oxidation states equal to -2 the charge of the ion, rule 3. Consider K In K0 2, oxygen has a oxidation state. Although this seems unusual, it is acceptable because oxidation states are merely an imposed electron bookkeeping scheme, not an actual physical quantity. Identifying Redox Reactions We can use oxidation states to identify redox reactions, even between nonmetals.
For example, is the following reaction between carbon and sulfur a redox reaction? What element is reduced?
We can use the oxidation state rules to assign oxidation states to all elements on both sides of the equation. In terms of our electron bookkeeping scheme the assigned oxidation state , carbon loses electrons during the conversion of reactants to products and is oxidized. During the conversion of reactants to products, sulfur changes from an oxidation state of 0 to an oxidation state of In terms of our electron bookkeeping scheme, sulfur gains electrons and is reduced.
If one substance loses electrons oxidation , then another substance must gain electrons reduction. A substance that causes the oxidation of another substance is called an oxidizing agent. Oxygen, for example, is an excellent oxidizing agent because it causes the oxidation of many substances. In a redox reaction, the oxidizing agent is always reduced. A substance that causes the reduction of another substance is called a reducing agent. Hydrogen, for example, as well as the group 1 and group 2 metals because of their tendency to lose electrons are excellent reducing agents.
In a redox reaction, the reducing agent is always oxidized. You will learn more about redox reactions below, including how to balance them. For now, you need to be able to identify redox reactions, as well as oxidizing and reducing agents, according to the following guidelines: Remember that a reduction is a reduction in I oxidation state. For each oxidation-reduction reaction, identify the oxidizing agent and the reducing agent. This is an acid- base or neutralization reaction.
Combustion reactions are redox reactions. For all redox reactions, identify the oxidizing agent and the reducing agent. Most home kits for hair bleaching contain hydrogen peroxide H 20 2 , an excellent oxidizing agent. When applied to hair, hydrogen peroxide oxidizes melanin, the dark pigment that gives hair its colour.
Melanin is an oligomer of 5,6-dihydroxyindole and 5,6-dihydroxyindolecarboxylic acid, which means that these two molecules are Linked together to make chains of varying lengths. The structure is highly conjugated, meaning that it has many alternating single and double bonds. These kinds of organic structures often absorb visible Light and give rise to colours. We will cover this in Chapter This reduces the number of alternating single and double bonds and removes the colour, leaving the hair with the fam iliar bleached look.
For example, protein molecules in hair contain -SH groups called thiols. Hydrogen peroxide oxidizes these thiol groups to sulfonic acid groups, -S03H.
The oxidation of thiol groups to sulfonic acid groups causes changes in the proteins that compose hair, making the hair more brittle and more likely to tangle.
Consequently, people with heavily bleached hair generally use conditioners containing compounds that form thin, lubricating coatings on individual hair shafts. These coatings prevent tangling and make hair softer and more manageable.
Question The following is a reaction of hydrogen peroxide with an alkene: Can you see why this reaction is a redox reaction? Can you identify the oxidizing and reducing agents? Balancing redox reactions can be more complicated than balancing other types of reactions because both the mass or number of each type of atom and the charge must be balanced. Redox reactions occurring in aqueous solutions can be balanced by using a special procedure called the half-reaction method of balancing.
In this procedure, the overall equation is broken down into two half-reactions: one for oxidation and one for reduction. The half-reactions are balanced individually and then added together. The steps differ slightly for reactions occurring in acidic and in basic solution. The following example demonstrates the method used for an acidic solution, and Example 4.
Assign oxidation states to all atoms and identify the substances being oxidized and reduced. This step simply allows you to categorize, with confidence, the half-reactions as oxidation or reduction in the next step. Mn is the oxidizing agent.
Separate the overall reaction into two halfreactions: one for oxidation and one for reduction. All elements other than 0 and H are balanced, so proceed to balance 0 and then H. The oxidation half-reaction does not contain 0 or H, so it remains the same for this step. All elements should now be balanced. Balance each half-reaction with respect to charge by adding electrons. Make the sum of the charges on both sides of the equation equal by adding as many electrons as necessary.
Add the two half-reactions together, cancelling electrons and other species as necessary. Verify that the reaction is balanced both with respect to mass and with respect to charge.
Make the number of electrons in both halfreactions equal by multiplying one or both half-reactions by a small whole number. SOLUTION To balance redox reactions occurring in basic solution, follow the half-reaction method outlined above for acidic solutions, but add an extra step to neutralize the W with as shown in step I below.
Verify that the reaction is balanced. For example, hydrogen peroxide H20 2 decomposes to form H 20 and 0 2. Assign oxidation states to help categorize the half-reactions. Separate the overall reaction into half-reactions. Balance each half-reaction with respect to charge.
Make the number of electrons in both equations the same by multiplying each by a small whole number. Add the half-reactions together and make necessary cancellations. In this case, we can divide each stoichiometric coefficient by a factor of two. Verify that the reaction is balanced with respect to mass and charge. A balanced chemical equation provides the exact relationship between the amount of reactant and the amount of product.
For example, in a combustion reaction, the chemical equation provides a relationship between the amount of fuel burned and the amount of carbon dioxide emitted. In the following discussion, we use octane a component of gasoline as our fuel. The balanced equation for the combustion of octane is: The balanced equation shows that 16 C0 2 molecules are produced for every 2 molecules of octane burned, or that 8 C02 molecules are produced for every mole of octane burned.
We can extend this numerical relationship between molecules to the amounts in moles as follows: The coefficients in a chemical reaction specify the relative amounts in moles of each of the substances involved in the reaction. In other words, from the equation, we know that eight moles of C02 are produced for every mole of octane burned. The use of the numerical relationships between chemical amounts in a balanced chemical equation are called reaction stoichiometries.
Stoichiometry allows us to predict the amounts of products that will form in a chemical reaction based on the amounts of reactants that react. Stoichiometry also allows us to determine the amount of reactants necessary to form a given amount of product.
These calculations are central to chemistry, allowing chemists to plan and carry out chemical reactions in order to obtain products in the desired quantities. Making Molecules: Mole-to-Mole Conversions A balanced chemical equation is simply a "recipe" for how reactants combine to form products. From our balanced equation for the combustion of octane, for example, we can write the following stoichiometric ratio: 1 mol C 8H 18 : 8mol C02 We can use this ratio to determine how many moles of C0 2 form when a given number of moles of C8H 18 burns.
A typical car or small truck requires Suppose we burn this entire tank of gas, mol of C8H 18; how many moles ofC02 form? We use the ratio from the balanced chemical equation. Making Molecules: Mass-to-Mass Conversions Respiration is a chemical reaction where glucose reacts with oxygen to form carbon dioxide and water: Let's estimate the mass of C02 that is produced by respiration of the glucose equivalent to the sugar in one chocolate bar, approximately The calculation is similar to the one done in the previous section, but this time we are given the mass of fuel C6H 6 instead of the number of moles.
Consequently, we must first convert the mass in grams to the amount in moles. The general conceptual plan for calculations where you are Stoichiometry is pronounced I stoy-kee-om-e-tree.
We use the molar mass of A to convert from the mass of A to the amount of A in moles. Then, we use the appropriate ratio from the balanced chemical equation to convert from the amount of A in moles to the amount of B in moles.
Finally, we use the molar mass of B to convert from the amount of B in moles to the mass of B. To calculate the mass of C0 2 produced from the respiration of Assuming that there is more than enough water present to react with all of the C02, what mass of glucose in grams can the plant synthesize from the C02?
SORT The problem gives the mass of carbon dioxide and asks you to find the mass of glucose that can be produced. From the chemical equation, d educe the relationship between moles of carbon dioxide and moles of glucose. Use the molar masses to convert between grams and moles.
GIVEN: Begin with g C0 2 and use the conversion factors to arrive at g C6 H 6. The magnitude of the answer This is reasonable because each carbon in C02 has two oxygen atoms associated with it, while in C6H 6 , each carbon has only one oxygen atom and two hydrogen atoms which are much lighter than oxygen associated with it.
Therefore, the mass of glucose produced should be less than the mass of carbon dioxide for this reaction. Assuming that there is adequate 0 2 and H2 0 , what mass of HN03 , in kg, can form from this amount of N0 2 pollutant?
Which diagram best represents the amount of sodium required to completely react with all of the oxygen in the flask, according to the above equation? We will use the combustion of propane C3H 8 , the most common barbeque fuel, as our example. What is the maximum amount of C02 that can be produced from the limiting reactant the theoretical yield?
First we must calculate the number of C02 molecules that can be made from 2 molecules of C3H 8 : -. The resulting solution will have a concentration of 3. The magnitude of the answer is reasonable because the solution is diluted from Therefore, the volume should increase by a factor of five. Solution Stoichiometry In Section 4. In aqueous reactions, quantities of reactants and products are often specified in terms of volumes and concentrations.
We can use the volume and concentration of a reactant or product to calculate its amount in moles. We can then use the stoichiometric coefficients in the chemical equation to convert to the amount of another reactant or product in moles. The general conceptual plan for these kinds of calculations begins with the volume of a reactant or product: Volume A.. Amount A in moles AmountB in moles VolumeB We make the conversions between solution volumes and amounts of solute in moles using the molarities of the solutions.
We make the conversions between amounts in moles of A and B using the stoichiometric coefficients from the balanced chemical equation. The following example demonstrates solution stoichiometry.
You are asked to find the volume of KC! The molar concentrations of the KC! The stoichiometric coefficients from the balanced equation are used to convert between number of moles of Pb N03h and number of moles of KC!.
GIVEN: 0. Unon 1 L KCI solution 0. The magnitude 0. Since the concentrations of the two solutions are not very different 0. The substances on the left-hand side of a chemical equation are called the reactants, and the substances on the right-hand side are called the products. Chemical equations are balanced when the number of each type of atom on the left side of the equation is equal to the number on the right side.
In oxidation-reduction reactions, one substance transfers electrons to another substance. The substance that loses electrons is oxidized, and the substance that gains them is reduced. An oxidation state is a fictitious charge given to each atom in a redox reaction by assigning all shared electrons to the atom with the greater attraction for those electrons.
Oxidation states are an imposed electronic bookkeeping scheme, not an actual physical state. The oxidation state of an atom increases upon oxidation and decreases upon reduction. A combustion reaction is a specific type of oxidation- reduction reaction in which a substance reacts with oxygen-emitting heat and forming one or more oxygen-containing products. Aqueous Solutions and Solubility 4. Solutes that completely dissociate or completely ionize in the case of acids to ions in solution are strong electrolytes and are good conductors of electricity.
Solutes that only partially dissociate or partially ionize are weak electrolytes, and solutes that do not dissociate or ionize at all are nonelectrolytes. A substance that dissolves in water to form a solution is soluble. The solubility rules are an empirical set of guidelines that help predict the solubilities of ionic compounds; these rules are especially useful in Section 4. Reaction Stoichiometry 4. Reaction stoichiometry allows us to predict, for example, the amount of product that can be formed for a given amount of reactant, or how much of one reactant is required to react with a given amount of another.
Aqueous reactions, such as precipitation reactions, can be represented with a molecular equation, which shows the complete neutral formula for each compound in the reaction. Alternatively, a reaction can be represented with a complete ionic equation, which shows the di ssociated nature of the aqueous ionic compounds.
Finally, a third representation is the net ionic equation, in which the spectator ions-those that do not change in the course of the reaction-are left out of the equation. When a chemical reaction actually occurs, the reactants are usually not present in the exact stoichiometric ratios specified by the balanced chemical equation.
The limiting reactant is the one that is available in the smallest stoichiometric quantity-it will be completely consumed in the reaction and it limits the amount of product that can be made. Any reactant that does not limit the amount of product is said to be in excess.
The amount of product that can be made from the limiting reactant is the theoretical yield. The actual yield-always equal to or less than the theoretical yield-is the amount of product that is actually made when the reaction is carried out. The percentage of the theoretical yield that is actually produced is the percent yield. Acid-Base Reactions 4. In an acid-base reaction, the acid and base neutralize each other, producing water or in some cases, a weak electrolyte. In gas-evolution reactions, the acid and base combine in solution and a gas is produced.
Solution Concentration and Solution Stoichiometry 4. We can use the molarities and volumes of reactant solutions to predict the amount of product that will form in an aqueous reaction. What is reaction stoichiometry? What is the significance of the coefficients in a balanced chemical equation? In a chemical reaction, what is the limiting reactant?
The theoretical yield? The percent yield? What do we mean when we say a reactant is in excess? The percent yield is normally calculated using the actual yield and theoretical yield in units of mass g or kg. Would the percent yield be different if the actual yield and theoretical yield were in units of amount moles?
What is an aqueous solution? What is the difference between the solute and the solvent? What is molarity? How is it useful? Explain how a strong electrolyte, a weak electrolyte, and a nonelectrol yte differ.
Explain the difference between a strong acid and a weak acid. What does it mean for a compound to be soluble? What are the solubility rules? How are they useful? What cations and anions have compounds that are usually soluble? What are the exceptions? What anions have compounds that are mostly insoluble? What is a precipitation reaction? Give an example. How can you predict whether a precipitation reaction will occur upon mixing two aqueous solutions? Explain how a molecular equation, a complete ionic equation, and a net ionic equation differ.
What are the Arrhenius definitions of an acid and a base? What is an acid-base reaction? Why can you not change the subscripts on the chemical formulas in order to balance a chemical reaction? What is a gas-evolution reaction? What reactant types give rise to gas-evolution reactions?
What is an oxidation-reduction reaction? What are oxidation states? How can oxidation states be used to identify redox reactions? What happens to a substance when it becomes oxidized? In a redox reaction, which reactant is the oxidizing agent? The reducing agent? What is a combustion reaction? Why are they important? Problems by Topic Writing and Balancing Chemical Equations Q Sulfuric acid is a component of acid rain formed when gaseous sulfur dioxide pollutant reacts with gaseous oxygen and Liquid water to form aqueous sulfuric acid.
Write a balanced chemical equation for this reaction. Nitric acid is a component of acid rain that forms when gaseous nitrogen dioxide pollutant reacts with gaseous oxygen and liquid water to form aqueous nitric acid. When iron rusts, solid iron reacts with gaseous oxygen to form solid iron III oxide. G Write a balanced chemical equation for the fermentation of sucrose C 12H 22 0 11 by yeasts in which the aqueous sugar reacts with water to form aqueous ethyl alcohol C2 H5 0H and carbon dioxide gas.
Write a balanced equation for the photosynthesis reaction in which gaseous carbon dioxide and liquid water react in the presence of chlorophyll to produce aqueous glucose C6 H 6 and oxygen gas. Write a balanced chemical equation for each reaction: a. Solid lead Il sulfide reacts with aqueous hydrobromic acid to form solid lead Il bromide and dihydrogen monosulfide gas. Gaseous carbon monoxide reacts with hydrogen gas to form gaseous methane CH 4 and Liquid water.
Aqueous hydrochloric acid reacts with solid manganese IV oxide to form aqueous manganese Il chloride, liquid water, and chlorine gas. Liquid pentane C5H 12 reacts with gaseous oxygen to form carbon dioxide and liquid water. Solid copper reacts with solid sulfur S 8 to form solid copper! Solid iron Ill oxide reacts with hydrogen gas to form solid iron and liquid water.
Sulfur dioxide gas reacts with oxygen gas to form sulfur trioxide gas. Gaseous ammonia NH 3 reacts with gaseous oxygen to form gaseous nitrogen monoxide and gaseous water. Balance each chemical equation: a. CsCl b. CH 30H c. Ca N02 z d. C6H 12 06 Classify each compound as a strong electrolyte or nonelectrolyte: a. MgBr2 b. C12H 11 c. Na2C03 d. KOH G Determine whether each compound is soluble or insoluble.
If the compound is soluble, list the ions present in solution. AgN03 b. Pb C2H30 2h c. KN03 d. NH4 2S Determine whether each compound is soluble or insoluble. For the soluble compounds, list the ions present in solution. AgI b. Cu3 P04 z c. CoC0 3 d. K3P04 show the reaction of aqueous Hg2 N0 3 z with aqueous sodium chloride to form solid Hg2Cl2 and aqueous sodium nitrate. Lead ions can be removed from solution by precipitation with sulfate ions.
Suppose that a solution contains lead Il nitrate. Write complete ionic and net ionic equations to show the reaction of aqueous lead Il nitrate with aqueous potassium sulfate to form solid lead Il sulfate and aqueous potassium nitrate. Write balanced molecular and net ionic equations for the reaction between nitric acid and calcium hydroxide. G Precipitation Reactions G Complete and balance each equation.
Complete and balance each equation. Write a molecular equation for the precipitation reaction that occurs if any when each pair of aqueous solutions is mixed. Write balanced complete ionic and net ionic equations for each reaction: a. Suppose that a solution contains aqueous Hg2 N03 z. Write complete ionic and net ionic equations to CD Complete and balance each acid-base equation : a.
Complete and balance each acid-base equation: a. Complete and balance each gas-evolution equation: a. H 2S Assign oxidation states to each atom in each element, ion, or compound: a. CuC1 2 d.
CH4 f. Cr20 iWhat is the oxidation state of Cr in each compound? CrO b. Cr03 c. Cr20 3 What is the oxidation state of Cl in each ion? Cl03f Determine whether each reaction is a redox reaction.
For each redox reaction, identify the oxidizing agent and the reducing agent. Determine whether each reaction is a redox reaction. Exercises 0 Complete and balance each combustion reaction equation: a. Complete and balance each combustion reaction equation: a. Calculate how many moles of N02 form when each quantity of reactant completely reacts: a.
Balance each redox reaction occurring in acidic aqueous solution. For each of the reactions, calculate the mass in grams of the product formed when Assume that there is more than enough of the other reactant. Consider the reaction: fl c. For each precipitation reaction, calculate how many grams of the first reactant are necessary to completely react with For the reaction, compute the theoretical yield of product in moles for each initial amount of reactants. Once the reaction has occurred as completely as possible, what amount in moles of the excess reactant is left?
For the reaction, compute the theoretical yield of product in grams for each initial amount of reactants. For the reaction, compute the theoretical yield of the product in grams for each initial amount of reactants. How many C02 molecules would be formed from the reaction mixture that produces the greatest amount of products?
For the reaction, find the limiting reactant for each initial amount of reactants. How many molecules of Cl2 would be formed from the reaction mixture that produces the greatest amount of products? Once the reaction has occurred as completely as possible, what mass in grams of the excess reactant is left? Calculate the molarity of each solution: a. Elemental phosphorus reacts with chlorine gas according to the equation: A reaction mixture initially contains What volume of a 0. What mass of NaN0 3 in grams is needed?
The precipitate is filtered and dried and found to have a mass of Determine the limiting reactant, theoretical yield of PbCl2 , and percent yield for the reaction. Magnesium oxide can be made by heating magnesium metal in the presence of oxygen.
Determine the limiting reactant, theoretical yield, and percent yield for the reaction. How many moles of KCl are contained in each solution? A chemist wants to make 5. What mass of CaCl2 in grams should the chemist use? GI To what volume should you dilute To what volume should you dilute 25 mL of a Determine the limiting reactant, theoretical yield of urea, and percent yield for the reaction. Many compu ter chips are manufactured from silicon, which occurs in nature as Si When Si02 is heated to melting, it reacts with solid carbon to form liquid silicon and carbon monoxide gas.
In an industrial preparation of silicon, G What is the minimum amount of 6. What is the molarity of ZnCl 2 that forms when Assume a final volume of mL. Find the percent by mass of sodium chloride in a l. The density of the solution is l. People often use sodium bicarbonate as an antacid to neutralize excess hydrochloric acid in an upset stomach. What mass of hydrochloric acid in grams can 2.
Hint: Begin by writing a balanced equation for Chapter 4 Ch emical Reac t ion s and Sto ichiometry the reaction between aqueous sodium bicarbonate and aq ueous hydrochloric acid. Toilet bowl cleaners often contain hydrochloric acid, which dissolves the calcium carbonate deposits that accumulate within a toilet bowl.
What mass of calcium carbonate in grams can 3. Hint: Begin by writing a balanced equation for the reaction between hydrochloric acid and calcium carbonate.
A hydrochloric acid solution will neutralize a sodium hydroxide solution. Begin by writing a balanced chemical eq uation for the neutralization reaction. G The combustion of gasoline produces carbon dioxide and water. Assume gasoline to be pure octane C 8H 18 and calculate the mass in kilograms of carbo n dioxide that is added to the atmosphere per 1.
Hint: Begin by writing a balanced equation for the combustio n reaction. Many home barbeques are fuelled with propane gas C 3H8. What mass of carbon dioxide in kilograms is produced upon the complete combustion of Assume that the density of the liquid propane in the tank is 0.
Hint: Begin by writing a balanced equation for the combustion reaction. Once the reaction is complete, the student collects 1. Determine the limiting reactant, theoretical yield of aspirin, and percent yield for the reaction. The combustion of liquid ethanol C2H 50H produces carbon dioxide and water. After 4. Determine the limiting reactant, theoretical yield of H 20 , and percent yield for the reaction. Hint: W rite a balanced equation for the combustio n of ethanol. The hydrogen within the balloon reacts explosively with oxygen in the air to form water.
If the balloon is filled with a mixture of hydrogen and oxygen, the explosion is even lo uder than if the balloon is filled only with hydrogen-the intensity of the explosion depends on the relative amounts of oxygen and hydrogen within the balloon. Look at the molecular views representing different amounts of hyd rogen and oxygen in four different ball oons.
Based on the balanced chemical equation, which balloon will make the lo udest explosio n? Predict the products and write a balanced molecular equation for each reaction. One way to soften water is to add phosphates.
The phosphate ion forms insoluble precipitates with calcium and magnesium ions, removing them from solution. Suppose that a solution is 0. What mass of sodium phosphate would have to be added to 1. Assume complete reaction. An acid solution is 0. The addition of 1. The total mass of the precipitate is G The nitrogen in sodium nitrate and in ammonium sulfate is available to plants as fertilizer.
Which is the more economical source of nitrogen, a fertilizer containing Find the volume of 0. Identify the oxidizing agent and the reducing agent in this reaction. Find the mass of the gold salt that forms when a We prepare a solution by mixing 0. When you add sodium chloride to the solution, no precipitate forms. When you add sodium sulfate to the solution, a white precipitate forms.
You filter off the precipitate and add sodium carbonate to the remaining solution, producing another precipitate.
Which ions were present in the original solution? Write net ionic equations for the formation of each of the precipitates observed. When potassium chloride is added to the solution, a precipitate forms. The precipitate is fi ltered off, and potassium sulfate is added to the remaining solution, producing no precipitate.
When potassium carbonate is added to the remaining solution, a precipitate forms. An important reaction that takes place in a blast furnace during the production of iron is the formation of iron metal and COz from Fez03 and CO.
Find the mass of Fez03 required to form kg of iron. Find the amount of COz that forms in this process. What maximum mass of carbon dioxide is produced by the complete combustion of Titanium occurs in the magnetic mineral ilmenite FeTi03 , which is often fou nd mixed with sand.
The ilmenite can be separated from the sand with magnets. Find the mass of PH3 that forms from the reaction of 1. If the second reaction is carried out with an It is burned in excess Oz to form a mixture of water and carbon dioxide that contains 1.
Find the mass of CzHz in the original mixture. A mixture of Find the mass of PC1 3 formed. The addition of0.
Find the mass of Agl in the precipitate. Lakes that have been acidified by acid rain HN0 3 and HzS04 can be neutralized by a process called liming, in which limestone CaC0 3 is added to the acidified water.
What mass of limestone in kg would completely neutralize a What minimum mass of succimer in milligrams is needed to bind all of the lead in a patient's bloodstream?
Suppose you work for a company interested in producing a self-rescue breathing apparatus based on the above reaction that would allow the user to survive for 10 minutes in an emergency situation. What are the important chemical considerations in designing such a unit? Estimate how much KOz would be required for the apparatus. Find any necessary additional information-such as human breathing rates-from appropriate sources.
We learned in Section 4. Suppose that a particular detergent mixture is designed to soften hard water that is 3. If the detergent requires using 0. Metallic aluminum reacts with MnOz at elevated temperatures to form manganese metal and aluminum oxide. A mixture of the two reactants is Find the theoretical yield in grams of manganese from the reaction of g of this mixture. Lead poisoning is a serious condition resulting from the ingestion of lead in food, water, or other environmental sources.
It affects the central nervous system, leading to a variety of symptoms such as distractibility, lethargy, and loss of motor coordination. Lead poisoning is treated with chelating agents, substances that bind to metal ions, allowing it to be eliminated in the urine. A modem chelating agent used for this purpose is succimer C4H6 0 4 Sz.
Suppose you are trying to 5 9 forms boric acid, H 3B Fusion of boric acid with sodium oxide forms a borate salt, NazB4 0 7. Without writing complete equations, find the mass in grams of B5H9 required to form g of the borate salt by this reaction sequence. A mixture of carbon and sulfur has a mass of 9. Complete combustion with excess Oz gives Find the mass of sulfur in the original mixture. Consider the reaction: 0 2 g - 2 K 20 s The molar mass of K is Without doing any calculations, determine which set of amounts best represents the mixture after the reactants have reacted as completely as possible.
Explain your reasoning. G The circle below represents 1. Fortunately, we live at the bottom of a vast ocean of air, held to Earth by gravity. We inhale a lungful of this air every few seconds, keep some of the molecules for our own needs, add some molecules our bodies no longer have a use for, and exhale the mixture back into the surrounding air.
The air around us is matter in the gaseous state. What are the fundamental properties of these gases? What laws describe their behaviour? What theory explains these properties and laws? The scientific method proceeds in this way-from observations to laws to theories-exactly the way we will proceed in this chapter. The gaseous state is the simplest and best-understood state of matter. In this chapter, we examine that state. The total weight of this air is about 25 kilograms.
How do you do it? The simple answer is pressure. You rely on your body's ability to create pressure differences to move air into and out of your lungs. Pressure is the force exerted per unit area by gas molecules as they strike the surfaces around 5. Just as a ball exerts a force when it bounces against a wall, a gaseous atom or molecule exerts a force when it collides with a surface.
The sum of all these molecular collisions is pressure-a constant force on the surfaces exposed to any gas. The total pressure exerted by a gas depends on several factors, including the concentration of gas molecules in the sample-the higher the concentration, the greater the pressure. When you inhale, the muscles that surround your chest cavity expand the volume of your lungs.
The expanded volume results in a lower concentration of gas molecules the number of molecules does not change, but since the volume increases, the concentration goes down. This in tum results in fewer molecular collisions, which results in lower pressure. If you have never realized the remarkable sensitivity of the world we can see to the world we cannot , you have missed out on a fundamental truth about our universe.
It robs you of an amazing and unforgettable experience of the world and the human ability to understand it. My second example demonstrates how science literacy helps you to be a better citizen. Although I am largely sympathetic to the environmental movement, a lack of science literacy within some sectors of that movement, and the resulting anti-environmental backlash, creates confusion that impedes real progress and opens the door to what could be misinformed policies.
I have also heard a liberal environmentalist say that we have to stop using hairspray because it is causing holes in the ozone layer that will lead to global warming. Well, the claim about volcanoes emitting more carbon dioxide than petroleum combustion can be refuted by the basic tools you will learn to use in Chapter 4 of this book.
As for hairspray depleting the ozone layer and thereby leading to global warming, the chlorofluorocarbons that deplete ozone have been banned from hairspray since , and ozone depletion has nothing to do with global warming anyway. People with special interests or axes to grind can conveniently distort the truth before an ill-informed public, which is why we all need to be knowledgeable. So this is why I think you should take this course. Not just to satisfy the requirement for your major, and not just to get a good job some day, but to help you to lead a fuller life and to make the world a little better for everyone.
I wish you the best as you embark on the journey to understand the world around you at the molecular level. The rewards are well worth the effort. Do you like this book? Please share with your friends, let's read it!! Search Ebook here:. Book Preface To the Student As you begin this course, I invite you to think about your reasons for enrolling in it. Designed by readallbooks. Download here Download Now here. Read Now Ads.
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