Chem Chapter 4

Front 1

Definition: Stoichiometry

Back 1

The numerical relationship between chemical amounts in a balanced chemical equation.

Front 2

Definition: Double displacement reaction (metathesis)

Back 2

When component ions of two ionic compounds trade partners

Front 3

Definition: Limiting reactant

Back 3

The reactant that limits the amount of product in a chemical reaction, it makes the least amount of the product.

Front 4

Finding the limiting reactant

Back 4

1. Convert mass of each reactant to moles

2. Multiply each by the conversion factor, the moles of reactant : the moles of the same product

3. The one that gives the lowest amount is the limiting reactant

Front 5

Definition: Excess reactants

Back 5

The reactants that do not limit the amount of product

Front 6

Definition: Theoretical yield

Back 6

The maximum amount of a product that can be made based on the amount of the limiting reactant

Front 7

Definition: Actual yield

Back 7

The amount of product actually produced by a chemical reaction (measured amount)

Front 8

Definition: Percent yield

Back 8

The percentage of the theoretical yield that was actually attained

Front 9

Finding the percent yield

Back 9

(actual yield)/(theoretical yield) then x100%

Front 10

Definition: Solution

Back 10

A homogeneous mixture of two substances

Front 11

Definition: Solvent

Back 11

The majority component in a solution

Front 12

Definition: Solute

Back 12

The minority component in a solution

Front 13

Definition: Aqueous solution

Back 13

A solution in which water acts as the solvent

Front 14

Definition: Dilute solution

Back 14

A solution that contains very little of the solute compared to the solvent

Front 15

Definition: Concentrated solution

Back 15

A solution that contains a large amount of solute relative to the solvent

Front 16

Definition: Molarity

Back 16

Symbol: M

The amount of solute (in mol) divided by the volume of the solution (in L)

Front 17

Formula for diluting a solution

Back 17

M1V1 = M2V2

M= molarity, V= volume

Works because the # of mol of the solute stays the same

Front 18

Conceptual plan for solution stoichiometry

Back 18

Volume A -> Moles A -> Moles B -> Volume B

Conversion factors: Molarity A (mol/L), mol A/mol B (from balanced equation), Molarity B (mol/L)

Front 19

Definition: Electrolytes

Back 19

Substances that dissolve in water to form solutions that conduct electricity (dissociate into ions)

Front 20

Definition: Strong electrolytes

Back 20

Substances that completely dissociate into ions when they dissolve in water

Front 21

Definition: Nonelectrolytes

Back 21

Compounds that do not dissociate into ions when dissolved in water

Front 22

Definition: Strong acid

Back 22

An acid that completely ionizes in solution

Front 23

Definition: Weak acids/ weak electrolytes

Back 23

Acids that do not completely ionize in water (in the chemical equation instead of an arrow there are opposing half arrows)

Front 24

Soluble vs insoluble

Back 24

Able to be dissolved in water vs not able

Front 25

Definition: Precipitation reactions

Back 25

Reactions in which a solid forms when solutions are mixed

Front 26

Definition: Molecular equation

Back 26

An equation showing the complete neutral formulas for each compound as if they existed as molecules, even when in solution

Front 27

Definition: Complete ionic equations

Back 27

Equations that list all of the ions present as either reactants or products. Strong acids are always represented as their component ions, weak electrolytes are not.

Front 28

Definition: Spectator ions

Back 28

Ions that appear unchanged on both sides of an ionic equation

Front 29

Definition: net ionic equations

Back 29

Equations that show only the species that actually change during the reaction

Front 30

Definition: Acid-base reaction/neutralization reaction

Back 30

A reaction in which an acid and base react and neutralize each other producing water or sometimes a weak electrolyte

Acid+Base --> Water+Salt

Front 31

Definition: Gas-evolution reaction

Back 31

A reaction in which a gas forms. Many gas-evolution reactions are also acid-base reactions

Front 32

Definition: Bases

Back 32

Substances that produce hydroxide (OH-) ions in water

Front 33

Definition: Polyprotic acids

Back 33

Acids that contain more than one ionizable proton and release them sequentially.

Ex: H2SO4, releases 2 H+, strong then weak

Front 34

Types of polyprotic acids

Back 34

Diprotic acids: have 2 H to start

Triprotic acids: have 3 H to start

Front 35

Six strong acids

Back 35

HCl, HI, HBr, HNO3, HClO4, H2SO4

Front 36

Definition: Titration

Back 36

In a titration a substance in a solution of known concentration is reacted with another solution with unknown concentration

Front 37

Definition: Titrant

Back 37

The solution with known concentration in a titration

Front 38

Definition: Analyte

Back 38

The solution with an unknown concentration in a titration

Front 39

Definition: Equivalence point (in titration)

Back 39

The point at which the number of moles of the titrant added matches the number of moles of the analyte. A.k.a end of titration

Front 40

Conceptual plan for titration (solving for M of analyte)

Back 40

1. L of titrant --> mol titrant --> mol analyte

2. mol analyte and L of analyte --> molarity analyte

Front 41

Types of compounds that undergo gas-evolution reactions

Back 41

Sulfides, carbonates and bicarbonates, sulfites and bisulfites, ammonium

Front 42

Four specific compounds that evolve gasses to know:

Back 42

CO3 2-, SO3 2-, S 2-, NH4 +

Front 43

Definition: Decomposition (in regards to gas-evolution reactions)

Back 43

When a product of a gas-evolution reaction is unstable and breaks down to form a gas and another product. The original product was an intermediate product.

Front 44

Definition: Oxidation-reduction reactions or redox reactions

Back 44

Reactions in which electrons transfer from one reactant to the other

Front 45

Definition: Oxidation

Back 45

Something loses electrons

Front 46

Definition: Reduction

Back 46

Something gains electrons

Front 47

Definition: Oxidation state

Back 47

A number given to each atom based on electron assignments.

- # of electrons attracted

+ # of electrons given up

(fractions are rare but possible)

Front 48

Definition: Oxidizing agent

Back 48

A substance that causes the oxidation of another substance. (Oxidizing agent is reduced)

Front 49

Definition: Reducing agent

Back 49

A substance that causes the reduction of another substance. (Reducing agent is oxidized)