Notes 7 – Compound Structure & Notes 7 – Compound Structure & Organic CompoundsOrganic Compounds

The Structure of CompoundsThe Structure of Compounds Substances that are compounds contain two or Substances that are compounds contain two or

more types of atoms chemically bonded more types of atoms chemically bonded togethertogether

Chemical bonds are the difference between a Chemical bonds are the difference between a mixture and a compoundmixture and a compound

The structure of a substance is created by the The structure of a substance is created by the bonding between atomsbonding between atoms

There are 2 main types of compound structure:There are 2 main types of compound structure:

1.1. Network StructureNetwork Structure

2.2. Molecular StructureMolecular Structure

What are network structures?What are network structures? Network structuresNetwork structures –compounds where every –compounds where every

particle is bonded to other particles throughout particle is bonded to other particles throughout the whole substancethe whole substance

Can be formed by the sharing of electrons OR Can be formed by the sharing of electrons OR the transfer of electrons between atomsthe transfer of electrons between atoms

Some substances are networks of ions held Some substances are networks of ions held together by ionic bonds (ionic networks)together by ionic bonds (ionic networks) Ex. Salt (NaCl)Ex. Salt (NaCl)

Some substances are networks of molecules Some substances are networks of molecules held together by covalent bonds (covalent held together by covalent bonds (covalent networks)networks) Ex. Quartz (SiOEx. Quartz (SiO22))

Properties of Network StructuresProperties of Network Structures Extremely strong structuresExtremely strong structures High melting pointsHigh melting points

NaCl melts at 801 °C NaCl melts at 801 °C SiOSiO22 melts at 1700 °C melts at 1700 °C

Solids at room temperatureSolids at room temperature Can be dissolved in waterCan be dissolved in water Covalently bonded network structures are Covalently bonded network structures are

extremely hard extremely hard Ex. DiamondEx. Diamond

What are molecular structures?What are molecular structures? Molecular structuresMolecular structures – compounds – compounds

made of covalently bonded molecules that made of covalently bonded molecules that are weakly attracted to one anotherare weakly attracted to one another Ex. Water (HEx. Water (H22O), Glucose (CO), Glucose (C66HH1212OO66))

Can only be formed by the sharing of Can only be formed by the sharing of electrons between atomselectrons between atoms

Individual molecules in the substance are Individual molecules in the substance are attracted to each other but not strongly attracted to each other but not strongly connectedconnected

Properties of Molecular StructuresProperties of Molecular Structures Not very strong structuresNot very strong structures Low melting pointsLow melting points

HH22O melts at 0 °C O melts at 0 °C

COCO22 melts at -78 °C melts at -78 °C

Sucrose (sugar), CSucrose (sugar), C1212HH2222OO1111 melts at 185 °C melts at 185 °C Usually liquids or gases at room temperatureUsually liquids or gases at room temperature

Ex. water, vegetable oil, carbon dioxide, Ex. water, vegetable oil, carbon dioxide, methanemethane

Sometimes solids at room temperatureSometimes solids at room temperature Ex. sugar, plastic, wax, fatsEx. sugar, plastic, wax, fats

What are organic compounds?What are organic compounds? Organic compoundOrganic compound – a covalently – a covalently

bonded compound made of molecules that bonded compound made of molecules that contain carboncontain carbon Always have a molecular structureAlways have a molecular structure Usually contain hydrogen as well as carbonUsually contain hydrogen as well as carbon May contain other non-metals such as May contain other non-metals such as

oxygen, nitrogen, sulfur, or phosphorousoxygen, nitrogen, sulfur, or phosphorous Come from living organisms and the remains Come from living organisms and the remains

of dead organisms of dead organisms Ex. sugar, cellulose, insulin, protein, DNA, Ex. sugar, cellulose, insulin, protein, DNA,

coal, petroleumcoal, petroleum

The Versatility of Carbon AtomsThe Versatility of Carbon Atoms Carbon atoms have a valence of 4Carbon atoms have a valence of 4 In order to become stable, carbon atoms In order to become stable, carbon atoms

can form up to 4 covalent bondscan form up to 4 covalent bonds One carbon atom might form:One carbon atom might form:

4 single covalent bonds4 single covalent bonds 2 single and 1 double covalent bond2 single and 1 double covalent bond 2 double covalent bonds2 double covalent bonds 1 triple and 1 single covalent bond1 triple and 1 single covalent bond

Carbon atoms can form an large variety of Carbon atoms can form an large variety of molecules (chains, rings, branched chains)molecules (chains, rings, branched chains)

What are hydrocarbons?What are hydrocarbons?

HydrocarbonHydrocarbon – an organic compound – an organic compound made of carbon and hydrogenmade of carbon and hydrogen

Two common types of hydrocarbons are Two common types of hydrocarbons are alkanesalkanes and and alkenesalkenes AlkanesAlkanes – hydrocarbons with only single – hydrocarbons with only single

covalent bondscovalent bonds AlkenesAlkenes – hydrocarbons with at least one – hydrocarbons with at least one

double covalent bonddouble covalent bond

Naming HydrocarbonsNaming Hydrocarbons The prefix indicates the number The prefix indicates the number

of carbon atoms in the moleculeof carbon atoms in the molecule The suffix indicates the type of The suffix indicates the type of

bonds between the carbon atomsbonds between the carbon atoms ane = single bondsane = single bonds ene = at least one double ene = at least one double

bondbond Ex. pentaneEx. pentane

A 5 carbon molecule (pent) A 5 carbon molecule (pent) with all single bonds (ane)with all single bonds (ane)

Ex. PropeneEx. Propene A 3 carbon molecule (prop) A 3 carbon molecule (prop)

with one double bond (ene)with one double bond (ene)

methmeth = 1= 1

etheth = 2= 2

propprop = 3= 3

butbut = 4= 4

pentpent = 5= 5

hexhex = 6= 6

hepthept = 7= 7

octoct = 8= 8

nonnon = 9= 9

decdec = 10= 10

Hydrocarbon Prefixes

Methane CHMethane CH44

Ethane CEthane C22HH66

Propane CPropane C33HH88

Ethene CEthene C22HH44

Propene CPropene C33HH66

SamplesSamples What would be the name of a hydrocarbon with 8 What would be the name of a hydrocarbon with 8

carbon atoms and one double bond?carbon atoms and one double bond? 8 = oct8 = oct double bond = enedouble bond = ene octeneoctene

Describe the structure of Describe the structure of nonanenonane non = 9non = 9 ane = single bondsane = single bonds A 9 carbon hydrocarbon with all single A 9 carbon hydrocarbon with all single

bondsbonds

What are alcohols?What are alcohols?

AlcoholAlcohol – an organic compound that is – an organic compound that is made of carbon, hydrogen, and an oxygen made of carbon, hydrogen, and an oxygen atomatom

Alcohols have “OH” groups (an oxygen Alcohols have “OH” groups (an oxygen bonded to a hydrogen)bonded to a hydrogen)

Alcohols are named just like alkanes and Alcohols are named just like alkanes and alkenes, but with “ol” at the endalkenes, but with “ol” at the end Ex. ethanolEx. ethanol Ethanol has two carbons (eth), single bonds Ethanol has two carbons (eth), single bonds

(an), and an –OH group (ol)(an), and an –OH group (ol)

Methanol CHMethanol CH33OHOH

Ethanol CEthanol C22HH55OHOH

Ethenol CEthenol C22HH33OHOH

What are isomers?What are isomers? IsomersIsomers – compounds that have the same – compounds that have the same

chemical formula, but different structureschemical formula, but different structures Ex. Ex. pentanepentane and and 2 methyl-butane2 methyl-butane

Both have formula CBoth have formula C55HH1212

Pentane - straight chain of 5 carbonsPentane - straight chain of 5 carbons 2 methyl-butane - chain of 4 carbons 2 methyl-butane - chain of 4 carbons

with a 1 carbon branchwith a 1 carbon branch