Chapter 5 chemical quantities and reactions
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Chapter 5 Chemical Quantities and Reactions. 5.8 Energy in Chemical Reactions. Molecules Must Collide for Reaction. Three conditions for a reaction to occur are: 1. collision: The reactants must collide. 2. orientation: The reactants must align properly to

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Chapter 5 Chemical Quantities and Reactions

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Chapter 5 chemical quantities and reactions

Chapter 5Chemical Quantities and Reactions

5.8

Energy in Chemical Reactions


Molecules must collide for reaction

Molecules Must Collide for Reaction

Three conditions for a reaction to occur are:

1. collision: The reactants must collide.

2. orientation: The reactants must align properly to

break and form bonds.

3. energy: The collision must provide the energy of

activation.


Exothermic reaction

Exothermic Reaction

In an exothermic reaction,

  • heat is released

  • the energy of the products is less than the energy of the reactants

  • heat is a product

    C(s) + 2H2(g) CH4(g) + 18 kcal


Endothermic reactions

Endothermic Reactions

In an endothermic reaction,

  • heat is absorbed

  • the energy of the products is greater than the energy of the reactants

  • heat is a reactant (added)

N2(g) + O2(g) + 43.3 kcal  2NO(g)


Learning check

Learning Check

Identify each reaction as exothermic or endothermic.

A. N2(g) + 3H2(g) 2NH3(g) + 22 kcal

B. CaCO3(s) + 133 kcal CaO(s) + CO2(g)

C. 2SO2(g) + O2(g) 2SO3(g) + heat


Solution

Solution

Identify each reaction as exothermic or endothermic.

A. N2(g)+ 3H2(g)2NH3(g)+ 22 kcalExothermic

B. CaCO3(s) + 133 kcal CaO(s) + CO2(g)

Endothermic

C. 2SO2(g) + O2(g) 2SO3(g) + heat

Exothermic


Reaction rate

Reaction Rate

The reaction rate

  • is the speed at which reactant is used up

  • is the speed at which product forms

  • increases when temperature rises because reacting molecules move faster, providing more colliding molecules with energy of activation

  • increases with increase in concentration of reactants


Catalyst

Catalyst

A catalyst

  • increases the rate of a reaction

  • lowers the energy of activation

  • is not used up during the reaction


Factors that increase reaction rate

Factors That Increase Reaction Rate


Learning check1

Learning Check

State the effect of each on the rate of reaction as

increases, decreases, or has no effect:

A. increasing the temperature

B. removing some of the reactants

C. adding a catalyst

D. placing the reaction flask in ice

E. increasing the concentration of one of the reactants


Solution1

Solution

State the effect of each on the rate of reaction as

increases, decreases, or has no effect:

A. increasing the temperatureincreases

B. removing some of the reactants decreases

C. adding a catalyst increases

D. placing the reaction flask in ice decreases

E. increasing the concentration of one of the reactant

increases


Chapter 10 introduction to organic chemistry alkanes

Chapter 10 Introduction to Organic Chemistry: Alkanes

10.5

Functional Groups


Elements in organic compounds

Elements in Organic Compounds

In organic molecules, carbon atoms bond

  • with four bonds

  • mostly with H and other C atoms

  • sometimes to O, N, S

  • sometimes to halogens F, Cl, and Br


Elements in organic compounds1

Elements in Organic Compounds


Functional groups

Functional Groups

Functional groups are

  • a characteristic feature of organic molecules that behave in a predictable way

  • composed of an atom or group of atoms

  • groups that replace a hydrogen atom in the corresponding alkane

  • a way to classify families of organic compounds


Alkenes alkynes and aromatic compounds

Alkenes, Alkynes, and Aromatic Compounds

Alkenes contain a double bond between adjacent carbon atoms.

Alkynes contain a triple bond.

Aromatic compounds contain a ring of six carbon atoms called benzene.


Comparing alkenes alkynes and aromatic compounds

Comparing Alkenes, Alkynes, and Aromatic Compounds


Learning check2

Learning Check

Identify the following compounds as an alkene, alkyne, or aromatic compound.

A.

B.

C.


Solution2

Solution

Identify the following compounds as an alkene, alkyne or aromatic compound.

A.aromatic

B.alkene

C.alkyne


Alcohols thiols and ethers

Alcohols, Thiols, and Ethers

An alcoholcontains the hydroxyl (−OH)functional group.

Athiol contains the thiol (−SH) functional group.

Anether contains an oxygen atom bonded to two carbon atoms

(COC) functional group.


Aldehydes and ketones

Aldehydes and Ketones

An aldehydecontains a carbonylgroup (C=O), which is a carbon atom with a double bond to an oxygen atom. The carbonyl carbon is attached to a hydrogen.

In a ketone,the carbon

of the carbonyl group (C=O) is attached to two carbon atoms.


Carboxylic acids and esters

Carboxylic Acids and Esters

Carboxylic acids contain the carboxyl group, which is a carbonyl group attached to a hydroxyl group.

COOH

An ester contains the

carboxyl group between carbon atoms.

COOCH3


Amines

Amines

Amines

  • have a functional group that contains a nitrogen atom

  • are derivatives of ammonia, NH3, in which one, two, or three hydrogen atoms are replaced with carbons


Amides

Amides

Amides

  • have an amine group instead of an OH group on the carbonyl carbon

  • are an important biological functional group, the

    simplest amide

    being urea


Classification of organic compounds

Classification of Organic Compounds


Learning check3

Learning Check

Classify each of the following as an alcohol, ether, aldehyde, ketone, carboxylic acid, ester, amine, or amide.

A.

B.

C.

D.

E.


Solution3

Solution

Classify each of the following as an alcohol, ether, aldehyde, ketone, carboxylic acid, ester, amine, or amide.

A.

B.

C.

D.

E.

alcohol

ether

amine

carboxylic acid

ester


Concept map organic compounds

Concept Map – Organic Compounds


Chapter 11 unsaturated hydrocarbons

Chapter 11 Unsaturated Hydrocarbons

11.1

Alkenes and Alkynes


Saturated hydrocarbons

Saturated Hydrocarbons

Saturated hydrocarbons

  • have the maximum number of hydrogen atoms attached to each carbon atom

  • are alkanes and cycloalkanes with single C–C bonds

    CH3–CH2–CH3


Unsaturated hydrocarbons

Unsaturated Hydrocarbons

Unsaturated hydrocarbons

  • have fewer hydrogen atoms attached to the carbon chain than alkanes

  • are alkenes with double bonds

  • are alkynes with triple bonds

Ball-and-stick models of ethene and ethyne show functional groups of double or triple bonds and bond angles.


Ethene ethylene

Ethene (Ethylene)

Ethene, or ethylene,

  • is the simplest alkene, with the formula C2H4

  • has two carbon atoms connected by a double bond

  • has two H atoms bonded to each C atom

  • is flat, with all the C and H atoms in the same plane

  • is a plant hormone used to accelerate the ripening of fruits


Fragrant alkenes

Fragrant Alkenes

The odors associated with the smell of lemons, oranges, roses, and lavender are due to volatile compounds that are synthesized by the plants.


Ethyne acetylene

Ethyne (Acetylene)

The simplest alkyne is ethyne, which has the common name of acetylene.

Acetylene is a fuel used in welding.


Naming alkenes and alkynes

Naming Alkenes and Alkynes

When the carbon chain of an alkene or alkyne has four or more C atoms, number the chain to give the lowest number to the first carbon in the double or triple bond.

CH2=CHCH2CH31-butene

1 2 3 4

CH3CH=CHCH32-butene

1 2 3 4

CH3CH2C=CCH32-pentyne

5 4 3 2 1


Guide to naming alkenes and alkynes

Guide to Naming Alkenes and Alkynes


Naming alkenes

Naming Alkenes

Using the IUPAC system, name the following compounds:

CH3 CH3 CH3

A. CH3CHH2C=CH2 B. H2C=CHCHCHCH3

Step 1Name the longest carbon chain that contains the double bond. Use the ending ene for alkenes.

CH3 CH3 CH3

A. CH3CHH2C=CH2 B. H2C=CHCHCHCH3

butene pentene


Naming alkenes1

Naming Alkenes

Step 2Number the longest carbon chain starting from the end nearer the double bond.

CH3 CH3 CH3

A. CH3CHH2C=CH2B. H2C=CHCHCHCH3

1-butene1-pentene

Step 3Give the location and name of each substituent (in alphabetical order) as a prefix to the alkene name.

CH3CH3 CH3

A. CH3CHH2C=CH2 B. H2C=CHCHCHCH3

3-methyl-1-butene3,4-dimethyl-1-pentene


Naming alkynes

Naming Alkynes

Using the IUPAC system, name the following compound:

CH3CH3

HC CCHCHCH3

Step 1Name the longest carbon chain that contains the triple bond. Use the ending yne for alkynes.

CH3 CH3

HC CCHCHCH3

pentyne


Naming alkynes1

Naming Alkynes

Step 2Number the longest carbon chain starting from the end nearer the triple bond.

CH3 CH3

HC CCHCHCH3

1-pentyne

Step 3Give the location and name of each substituent (in alphabetical order) as a prefix to the alkyne name.

CH3 CH3

HC CCHCHCH3 3,4-dimethyl-1-pentyne


Chapter 11 unsaturated hydrocarbons1

Chapter 11 Unsaturated Hydrocarbons

11.2

Cis–Trans Isomers


Cis and trans isomers

Cis and Trans Isomers

In an alkene, the double bond

  • is rigid

  • holds attached groups in fixed positions

  • makes cis–trans isomers possible


Cis trans isomers

Cis–Trans Isomers

In cis–trans isomers,

  • there is no rotation around the double bond in alkenes

  • groups attached to the double bond are fixed relative to each other

    You can make a “double bond” with your fingers with both thumbs on the same side or opposite from each other.


Cis trans isomers1

Cis–Trans Isomers

Two isomers are possible when the

groups attached to each side of

the double bond are different.

  • In a cis isomer, the alkyl groups are attached on one side of the double bond and H atoms are on the other side.

  • In the trans isomer, the groups and H atoms are attached on opposite sides.

Ball-and-stick models of the cis and trans isomers of 2-butene.


Cis trans isomerism

Cis–Trans Isomerism

  • Alkenes cannot have cis–trans isomers if a carbon atom in the double bond is attached to identical groups.

    Identical Identical

    2-Bromopropene1,1-Dibromoethene

    (not cis or trans) (not cis or trans)

H

H

Br

H


Cis trans isomers in nature

Cis–Trans Isomers in Nature

  • Insects emit tiny quantities of pheromones, which are chemicals that send messages.

  • The silkworm moth attracts other moths by emitting bombykol, which has one cis and one trans double bond.

Pheromones allow insects to attract mates from a great distance.


Naming cis trans isomers

Naming Cis–Trans Isomers

The prefix of cis or trans is placed in front of the alkene name when the compound is a cisortrans isomer.

cis trans

cis-1,2-dibromoethenetrans-1,2-dibromoethene


Learning check4

Learning Check

Name each, using cis or transprefixes when needed.


Solution4

Solution

Name each, using cis or trans prefixes when needed.

cis-1,2-dibromoethene

trans-2-butene

1,1-dichloropropene


Chapter 11 unsaturated hydrocarbons2

Chapter 11 Unsaturated Hydrocarbons

11.4

Polymers of Alkenes


Polymers

Polymers

Polymers are

  • large, long-chain molecules

  • found in nature, including cellulose in plants, starches in food, proteins, and DNA in the body

  • also synthetic, such as polyethylene and polystyrene, Teflon, and nylon

  • composed of small repeating units called monomers

  • made from reaction of small alkenes


Addition reactions polymerization

Addition Reactions: Polymerization

In polymerization, small repeating units called monomersjoin to form a long-chain polymer in an addition reaction.

monomer unit repeats

n


Common synthetic polymers

Common Synthetic Polymers

Synthetic polymers provide a wide variety of items that we use every day.


Common synthetic polymers polyethylene

Common Synthetic Polymers: Polyethylene

Polyethylene is made using an addition reaction with the monomer unit ethylene.

Common uses for polyethylene include plastic bottles, film, and insulation materials.


Common synthetic polymers polyvinylchloride

Common Synthetic Polymers: Polyvinylchloride

Polyvinylchloride, also known as PVC, is used for plastic pipes and tubing, garden hoses, and garbage bags.


Learning check5

Learning Check

Name the starting monomer and give its structure for each of the following polymers:

A. polyethylene

B. polyvinylchloride

C. polystyrene


Solution5

Solution

Name the starting monomer and give its structure for each of the following polymers:

A. polyethylene ethene

B. polyvinylchloride chloroethene

C. polystyrene phenylethene, styrene


Recycling plastics

Recycling Plastics

Recycling is simplified by using codes on plastic items.

1 PETE Polyethylene terephtalate

2 HDPEHigh-density polyethylene

3 PVPolyvinyl chloride

4 LDPELow-density polyethylene

5 PP Polypropylene

6 PSPolystyrene

7 OTHER Other plastic: fiberglass, polycarbonate, etc.


Chapter 11 unsaturated hydrocarbons3

Chapter 11 Unsaturated Hydrocarbons

11.5

Aromatic Compounds


Aromatic compounds

Aromatic Compounds

Benzene is

  • an aromatic compound

  • a ring of six C atoms and six H atoms

  • a flat ring structure drawn with three double bonds

  • represented by two structures because the electrons are shared among all the C atoms


Benzene structure

Benzene Structure

Benzene

  • has six electrons shared equally among the six C atoms

  • is also represented as a hexagon with a circle drawn inside


Aromatic compounds in nature and health

Aromatic Compounds in Nature and Health

Vanillin Aspirin

IbuprofenAcetaminophen


Naming aromatic compounds

Naming Aromatic Compounds

Aromatic compounds are named

  • with benzeneas the parent chain

  • with one side group named in front ofbenzene

    methylbenzenechlorobenzene


Some common names

Some Common Names

Some substituted benzene rings

  • have common names that have been in use for many years

  • with a single substituent use a common name or are named as a benzene derivative

    toluene aniline phenol

    (methylbenzene) (benzenamine) (hydroxybenzene)

Know only this structure from this slide


Learning check6

Learning Check

Identify the organic family for each:

A. CH3CH2CH=CH2

B.

C. CH3CCH

D.


Solution6

Solution

Identify the organic family for each:

A. CH3CH2CH=CH2 alkene

B. cycloalkane (alkane)

C. CH3CCH alkyne

D. aromatic


Chapter 12 organic compounds with oxygen and sulfur

Chapter 12 Organic Compounds with Oxygen and Sulfur

12.2

Properties of Alcohols and Ethers


Solubility of alcohols in water

Solubility of Alcohols in Water

Alcohols

  • contain polar OH groups and form hydrogen bonds with other alcohol molecules

  • that have one to three carbons are soluble in water

  • solubility in water decreases with increasing number of carbons


Solubility of ethers in water

Solubility of Ethers in Water

Ethers

  • do not have a polar OH group, but have a COC group

  • do not form hydrogen bonds

  • with less than four carbons are slightly soluble in water

  • with more than four carbons are not soluble in water


Solubility of alcohols and ethers in water

Solubility of Alcohols and Ethers in Water


Solubility of phenols

Solubility of Phenols

Phenols

  • are slightly soluble in water

  • have an OH group that can form hydrogen bonds with water

  • can react with water to produce phenoxide ions

  • were once used as antiseptics

+ H2O + H3O+


Learning check7

Learning Check

Indicate whether each of the following is soluble in water

and explain why.

A. CH3CH2CH2CH2CH2CH2OH

B. CH3OCH2CH3

C. CH3CH2OH


Solution7

Solution

Indicate whether each of the following is soluble in water

and explain why.

A. CH3CH2CH2CH2CH2CH2OH Not soluble

Alcohols with long carbon chains (nonpolar) are not soluble.

B. CH3OCH2CH3 Slightly soluble

Ethers with less than four carbons are only slightly soluble in water.

C. CH3CH2OH Soluble

Short-chain alcohols form hydrogen bonds with water.


Chapter 12 organic compounds with oxygen and sulfur1

Chapter 12 Organic Compounds with Oxygen and Sulfur

12.5

Properties of Aldehydes and Ketones

In Tollens’ test, a silver mirror forms when the oxidation of an aldehyde reduces silver ion to metallic silver. The silvery surface of a mirror is formed in a similar way.


Physical properties

Physical Properties

The polar carbonyl group provides dipole-dipole interactions.

+ -+ -

C=O C=O

Because the electronegative oxygen atom forms hydrogen bonds with water molecules, aldehydes and ketones with one to four carbons are very soluble.


Solubility in water

Solubility in Water

The electronegative O atom of the carbonyl group of aldehydes and ketones forms hydrogen bonds with water.


Learning check8

Learning Check

Indicate whether each is soluble or insoluble in water.

A. CH3—CH2—CH3

B. CH3—CH2—OH

O

||

C. CH3—CH2—CH2—C—H

O

||

D. CH3—C—CH3


Solution8

Solution

Indicate whether each is soluble or insoluble in water.

A. CH3—CH2—CH3insoluble

B. CH3—CH2—OH soluble

O

||

C. CH3—CH2—CH2—C—H soluble

O

||

D. CH3—C—CH3soluble


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