Chapter 4 - Chemical Quantities and Aqueous Reactions

Question 1

The coefficients in a chemical equation specify the relative amounts in ____ of each of the substances involved in the reaction.

Answer 1

moles

Question 2

The numerical relationships between chemical amounts in a balanced chemical equation are called reaction __________.

Answer 2

stoichiometry

Question 3

Stoichiometry allows us to predict the amounts of ______ that will form in a chemical reaction based on the amounts of _______ that react.

Answer 3

products, reactants

Question 4

Stoichiometry also allows us to determine the amount of _______ necessary to form a given amount of _______.

Answer 4

reactants, product

Question 5

The reactant that limits the amount of product in a chemical reaction is called the…

Answer 5

limiting reactant

Question 6

The limiting reactant is the reactant that makes the ____ amount of a product.

Answer 6

least

Question 7

The maximum amount of product that can be made in a chemical reaction based on the amount of limiting reactant is called the…

Answer 7

theoretical yield

Question 8

The amount of product actually produced by a chemical reaction is called the…

Answer 8

actual yield

Question 9

The actual yield is always ____ to or ____ than the theoretical yield because a small amount of product is usually lost to other reactions or does not form during a reaction.

Answer 9

equal to or less than

Question 10

The percentage of the theoretical yield that was actually attained, is calculated as the ratio of the actual yield to the theoretical yield, is called the…

Answer 10

percent yield

Question 11

How do you calculate percent yield?

Answer 11

(Actual yield/Theoretical yield)x100 = Percent yield

Question 12

The ______ reactant is the reactant that is completely consumed in a chemical reaction and limits the amount of a product.

Answer 12

limting

Question 13

The reactant in _____ is any reactant that occurs in a quantity greater than is required to completely react with the limiting reactant.

Answer 13

excess

Question 14

The ________ yield is the amount of product that can be made in a chemical reaction based on the amount of limiting reactant.

Answer 14

theoretical

Question 15

The _____ yield is the amount of product actually produced by a chemical reaction.

Answer 15

actual

Question 16

A homogenous mixture of two substances - such as salt and water - is a _______.

Answer 16

solution

Question 17

The majority component of a mixture is the ______, and the minority component is the ______.

Answer 17

solvent, solute

Question 18

An aqueous solution is one in which water acts as the ______.

Answer 18

solvent

Question 19

We can add just a little salt to water to make a ______ solution, one that contains a small amount of solute relative to the solvent.

Answer 19

dilute solution

Question 20

We can add a lot of salt to water to make a _________ solution, one that contains a large amount of solute relative to the solvent.

Answer 20

concentrated

Question 21

A common way to express solution concentration is ________ (__).

Answer 21

Molarity (M)

Question 22

Molarity (M) =

Answer 22

M = (amount of solute (in mol))/(volume of solution (in L))

Question 23

Molarity is a ratio of the amount of solute per liter of ______, NOT per liter of solvent.

Answer 23

solution

Question 24

What is the Solution Dilution equation?

Answer 24

M1V1 = M2V2

Question 25

M1V1 = M2V2, where M1 and V1 are the molarity and volume of the initial _________ solution, and M2 and V2 are the molarity and volume of the final ______ solution

Answer 25

concentrated, diluted

Question 26

When a solid is put into a liquid solvent, the attractive forces that hold the solid together ( the ______-______ interactions) compete with the attractive forces between the solvent molecules and the particles that compose the solid (the _______-______ interactions).

Answer 26

solute-solute interactions | solvent-solute interactions

Question 27

The attraction of Na+ and Cl- to water is based on the _____ nature of the water molecule.

Answer 27

polar

Question 28

Explain the dissolution of an ionic compound (sodium chloride dissolving in water).

Answer 28

The oxygen atom in water is electron-rich, giving it a partial negative charge. The hydrogen atoms are electron-poor, giving them a partial positive charge. As a result, the positively charged sodium ions are strongly attracted to the oxygen side of the water molecule (which has a partial negative charge), and the negatively charged chloride ions are attracted to the hydrogen side of the water molecule which has a partial positive side). In the case of NaCl, the attraction between the separated ions and the water molecules overcomes the attraction of sodium and chloride ions to each other, and the sodium chloride dissolves in the water.

Question 29

T/F: A salt solution conducts electricity while a sugar solution does not.

Answer 29

T

Question 30

The dissolved ions act as ______ carriers, allowing the solution to conduct electricity.

Answer 30

charge

Question 31

Substances that dissolve in water to form solutions that conduct electricity are _________.

Answer 31

electrolytes

Question 32

Substances such as sodium chloride that completely dissociate into ions when they dissolve in water are ______ __________.

Answer 32

strong electrolytes

Question 33

Compounds such as sugar that do not dissociate into ions when dissolved in water are called _____________.

Answer 33

nonelectrolytes

Question 34

Acids are molecular compounds, but they do ______ - form ____ - when they dissolve in water.

Answer 34

ionize, ions

Question 35

HCL is an example of a ______ _____, one that completely ionizes in a solution.

Answer 35

strong acid

Question 36

Since strong acids completely ionize in solution, they are also ______ __________.

Answer 36

strong electrolytes

Question 37

Many acids are ____ _____; they do not completely ionize in water.

Answer 37

weak acids

Question 38

A solution of a weak acid is composed mostly of the _________ acid - only a small percentage of the acid molecules ionize.

Answer 38

nonionized

Question 39

We represent the partial ionization of a weak acid with opposing ____ ______ between the reactants and the products.

Answer 39

half arrows

Question 40

When an ionic compound dissolves in water, the resulting solution contains not the intact ionic compound itself, but its component ____ dissolved in water. However, not all ionic compounds dissolve in water...

Answer 40

ions

Question 41

A compound is termed ______ if it dissolves in water and _______ if it does not.

Answer 41

soluble, insoluble

Question 42

The key to predicting precipitation reactions is to understand that only ________ compounds form precipitates.

Answer 42

insoluble

Question 43

In a precipitation reaction, two solutions containing ______ compounds combine and an ______ compound precipitates.

Answer 43

soluble, insoluble

Question 44

If the possible products are both ______, no reaction occurs and no precipitate forms.

Answer 44

soluble

Question 45

If one or both of the possible products are _______, a precipitation reaction occurs.

Answer 45

insoluble

Question 46

Which six ions are always soluble without exception?

Answer 46

Li+, Na+, K+, NH^4+, NO3-, C2H302-

Question 47

Cl-, Br-, and I- are always soluble except when paired with (3)...

Answer 47

Ag+, Hg2^2+,Pb^2+

Question 48

SO4^2- is always soluble except when paired with(5)...

Answer 48

Sr^2+, Ba^2+, Pb^2+, Ag+, Ca^2+

Question 49

OH- and S^2- are always insoluble except when paired with(4)...

Answer 49

Li+, Na+, K+, NH^4+

Question 50

CO3^2- and PO4^3- are always insoluble except when paired with(4)...

Answer 50

Li+, Na+, K+, NH^4+

Question 51

Equations which list all of the ions present as either reactant or products in a chemical reaction are _______ _____ _________.

Answer 51

complete ionic equations

Question 52

In the complete ionic equation, some of the ions in solution appear unchanged on both sides of the equation. These ions are called _______ ____ because they do not participate in the reaction.

Answer 52

spectator ions

Question 53

Equations that show only the species that actually change during the reaction are ___ _____ ________.

Answer 53

net ionic equations

Question 54

To write the net ionic equation, we remove the _________ ____, those that are unchanged on both sides of the equation.

Answer 54

spectator ions

Question 55

In an acid-base reaction, an ____ reacts with a ____ and the two neutralize each other, producing _____ (or in some cases a weak electrolyte).

Answer 55

acid, base, water

Question 56

An acid-base reaction is also called a ___________ reaction.

Answer 56

neutralization

Question 57

All antacids, regardless of the base they employ, have the same effect of _________ stomach acid and relieving heartburn through acid-base reactions.

Answer 57

neutralizing

Question 58

Acid: Substance that produces __ ions in aqueous solution Base: Substance that produces __ ions in aqueous solution

Answer 58

H+, OH-

Question 59

What is a hydronium ion?

Answer 59

H3O+

Question 60

According to the Arrhenius definition, NaOH is a base because it produces ___ ions in solution.

Answer 60

OH-

Question 61

________ acids contain more than one ionizable proton and release them sequentially.

Answer 61

Polyprotic

Question 62

A _______ acid is an acid such as H2SO4 (sulfuric acid) that contains within its molecular structure two hydrogen atoms per molecule capable of dissociating (i.e. ionizable) in water.

Answer 62

diprotic

Question 63

Acid-base reactions generally form water and an ionic compound - called a ____ - that usually remains dissolved in the solution.

Answer 63

salt

Question 64

What is the net ionic equation for many acid-base reactions?

Answer 64

H+(aq) + OH-(aq) ---> H2O(l) Acid + Base ---> Water + Salt

Question 65

In a ________, a substance in a solution of of known concentration is reacted with another substance in a solution of unknown concentration.

Answer 65

titration

Question 66

At the _________ _____ -- the point in the titration when the number of moles of OH- added equals the number of moles of H+ initially in a solution -- the titration is complete.

Answer 66

equivalence point

Question 67

The equivalence point is typically signaled by an ________, a dye whose color depends on the acidity or basicity of the solution.

Answer 67

indicator

Question 68

H2CO3 dissociates to form ___

Answer 68

CO2 + H2O

Question 69

H2SO3 dissociates to form ___

Answer 69

SO2 + H20

Question 70

NH4OH dissociates to form ___

Answer 70

NH3 + H20

Question 71

In a ___-_______ reaction, two aqueous solutions mix to form a gaseous product that bubbles out of solution.

Answer 71

gas evolution

Question 72

A fundamental definition of _________ is the loss of electrons.

Answer 72

oxidation

Question 73

A fundamental definition of ________ is the gain of electrons.

Answer 73

reduction

Question 74

What are the five rules for assigning oxidation states?

Answer 74

1. The oxidation state of an atom in a free element is 0. 2. The oxidation state of a monoatomic ion is equal to its charge. 3. The sum of the oxidation states of all atoms in: 3a. A neutral molecule or formula unit is 0. 3b. An ion is equal to the charge of the ion. 4. In their compounds, metals have positive oxidation states. ex: Group 1A metals ALWAYS have an oxidation state of +1. ex: Group 2A metals ALWAYS have an oxidation state of 2+. 5. In their compounds, nonmetals are assigned oxidation states according to the table (Fluorine, Hydrogen, Oxygen, Group 7A, Group 6A, Group 5A). Entries at the top of the table take precedence over entries at the bottom of the table.

Question 75

In a redox reaction, the reducing agent is always ________.

Answer 75

oxidized

Question 76

Combustion reactions are characterized by the reaction of a substance with __ to form one or more oxygen-containing compounds, often including ___

Answer 76

O2, H20