The The Chemistry of Chemistry of

LifeLifeChapter 2

vocabularyvocabulary

AtomAtom the most basic and smallest unit of the most basic and smallest unit of mattermatter– NucleusNucleus

center of the atomcenter of the atom holds protons and neutronsholds protons and neutrons

– Contains subatomic particlesContains subatomic particles called protons, electrons and neutronscalled protons, electrons and neutrons Discuss next diagramDiscuss next diagram

AtomsAtoms

Nucleus; Nucleus; Protons; + charge; mass = 1AMUProtons; + charge; mass = 1AMU Neutrons; no charge; mass = 1AMUNeutrons; no charge; mass = 1AMU

Electrons: - charge; no massElectrons: - charge; no mass

vocabularyvocabulary

ElementElement specific atoms of one type specific atoms of one type form pure substancesform pure substances

Over 100 elements/pure substances Over 100 elements/pure substances existexist CaCa calcium calcium HH hydrogen hydrogen OO oxygen oxygen NaNa sodium sodium CC carbon carbon

Periodic tablePeriodic table

Elements are organized in a table Elements are organized in a table and assigned a numberand assigned a number

NumberNumber atomic number atomic number TableTable periodic table periodic table

This your new friend…at least for this This your new friend…at least for this next unit!next unit!

Get use to itGet use to it

Atomic NumberAtomic Number Defines the elementDefines the element Is equal to the number of protonsIs equal to the number of protons Is equal to the number of electrons Is equal to the number of electrons

in a neutral atomin a neutral atom Always the whole numberAlways the whole number

6

CCarbon12.011

Section 2-1

An Element in the Periodic Table

Go to Section:

Atomic Number

Atomic Mass

Atomic MassAtomic Mass

Is equal to the number of protons Is equal to the number of protons and neutrons in the nucleus of the and neutrons in the nucleus of the atomatom

May not be a whole number on the May not be a whole number on the periodic tableperiodic table

In biology you may round up the In biology you may round up the mass number to a whole numbermass number to a whole number

To find the number of To find the number of NeutronsNeutrons

Atomic mass – atomic number = Atomic mass – atomic number = NeutronsNeutrons

Nonradioactive carbon-12 Nonradioactive carbon-13 Radioactive carbon-14

6 electrons6 protons6 neutrons

6 electrons6 protons8 neutrons

6 electrons6 protons7 neutrons

Isotopes of Carbon

Isotopes have the same number of protons and electrons but have a different number of neutrons

Time to play…

Candium isotope lab!!!

Energy LevelsEnergy Levels

1st 2e-

2nd 8e-

3rd 8e-

4th18e-

Valence ElectronsValence Electrons Outer level ElectronsOuter level Electrons Bonding ElectronsBonding Electrons

How are things kept How are things kept togethertogether

Ionic BondsIonic Bonds Transferring of electronsTransferring of electrons Create ionsCreate ions Opposite charged particles are attracted to each Opposite charged particles are attracted to each

otherother Electrons are gained/lostElectrons are gained/lost

Covalent bondsCovalent bonds Can create slightly different chargesCan create slightly different charges Strongest chemical bondStrongest chemical bond Orbitals/shells overlap and electrons bounce back Orbitals/shells overlap and electrons bounce back

and forthand forth Van der Waals forcesVan der Waals forces

Happens when molecules are super close togetherHappens when molecules are super close together Hydrogen bonding-weak bondsHydrogen bonding-weak bonds

Drawing molecules showing Drawing molecules showing Ionic BondingIonic Bonding

Draw all atoms showing protons, and Draw all atoms showing protons, and electrons in their energy levelselectrons in their energy levels

Decide which electrons must be Decide which electrons must be transferred in order to fill all of the transferred in order to fill all of the atoms outer levelatoms outer level

Draw the electrons being transferredDraw the electrons being transferred Show the resulting charge on the IonsShow the resulting charge on the Ions

Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+) Chloride ion (Cl-)

Transferof electron

Protons +11Electrons -11Charge 0

Protons +17Electrons -17Charge 0

Protons +11Electrons -10Charge +1

Protons +17Electrons -18Charge -1

Ionic Bonding

Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+) Chloride ion (Cl-)

Transferof electron

Protons +11Electrons -11Charge 0

Protons +17Electrons -17Charge 0

Protons +11Electrons -10Charge +1

Protons +17Electrons -18Charge -1

Section 2-1

Ionic Bonding

Draw the following Draw the following molecules showing them molecules showing them

form ionic bondsform ionic bonds KFKF MgClMgCl22

Chemical formulas Chemical formulas

COCO2 2 3 Atoms3 Atoms

HH22OO 3 Atoms3 Atoms

Ca(OH)Ca(OH)2 2 5 Atoms5 Atoms

2C2C66HH1212OO6 6 48 atoms48 atoms

Covalent BondingCovalent Bonding

Sharing of electronsSharing of electrons No ions are formedNo ions are formed Sharing of electrons holds it Sharing of electrons holds it

together.together.

Guided/independent Guided/independent practicepractice

Chemistry worksheet…time to think!Chemistry worksheet…time to think!

WaterWater

Most abundant compound found in Most abundant compound found in living things.living things.

Water is a molecule (HWater is a molecule (H22O)O) Water is a polar molecule. (unequal Water is a polar molecule. (unequal

sharing of electrons)sharing of electrons) Hand out chemistry worksheet!Hand out chemistry worksheet!

WaterWater FactsFacts

It is a neutral moleculeIt is a neutral molecule Water is the single most abundant compound Water is the single most abundant compound

on earthon earth It expands when it freezesIt expands when it freezes It floats when frozenIt floats when frozen

What advantage does this play in the survival of fish What advantage does this play in the survival of fish and plantsand plants

75% of earth is water75% of earth is water The human body is 70% waterThe human body is 70% water Ph of 7.0Ph of 7.0

Properties of WaterProperties of Water

Its PolarIts Polar It has a negative end and a positive endIt has a negative end and a positive end Uneven sharing of electronsUneven sharing of electrons

High heat capacityHigh heat capacity Absorb Absorb

Hydrogen bondsHydrogen bonds Because of the uneven charge water Because of the uneven charge water

atoms can attract each otheratoms can attract each other Cohesion: attraction between Cohesion: attraction between

molecules of the same substancemolecules of the same substance Insects walking on waterInsects walking on water

Adhesion: attraction between Adhesion: attraction between molecules of different substances molecules of different substances Water drawn up a plant (capillary action)Water drawn up a plant (capillary action)

Hydrogen Hydrogen BondingBonding

Water demoWater demo

Water labWater lab

Acids, Bases, and the pH Acids, Bases, and the pH scalescale

Water is the universal solventWater is the universal solvent Most compounds will dissolve in waterMost compounds will dissolve in water Remember 75% of most animals are waterRemember 75% of most animals are water

HH220 0 →→ H H++ + OH + OH--

Water Water →→ Hydrogen ion + Hydroxide ion Hydrogen ion + Hydroxide ion Only about one water molecule in 55 Only about one water molecule in 55

million will form a hydrogen ionmillion will form a hydrogen ion HH++ = OH = OH-- , so water is always neutral , so water is always neutral

PH scale – measures the PH scale – measures the concentration of H+ concentration of H+ and OH- ions.and OH- ions.

Ranges from 0-14Ranges from 0-14 At 7 the concentration of H+ and At 7 the concentration of H+ and

OH- is equal. (pure water)OH- is equal. (pure water) Acid – H+ ions, 0-6Acid – H+ ions, 0-6 Alkaline or base- OH- ions, 8-14Alkaline or base- OH- ions, 8-14 Each step represents a factor of 10Each step represents a factor of 10

Oven cleaner

Bleach

Ammonia solution

Soap

Sea water

Human bloodPure waterMilkNormalrainfall

Acid rainTomatojuice

Lemon juice

Stomach acid

NeutralIn

crea

sing

ly B

asic

Incr

easi

ngly

Aci

dic

pH Scale

Go to Section:

Acids

Any compound that gives off a hydrogen ion (H+) in a solution.

– HCl

– Stomach acid

– Lemon juice

– Tomato juice

Bases

Any compound that will produce hydroxide ions (OH-) in a solution.

– Human blood

– Sea water

– Oven cleaner

– Bleach

– soap

Time to play…

Ph lab

Buffers

Facts– Most cells in animals must generally be kept at a pH level between 6.5 and

7.5• Human blood has a pH of 7.4

– If the body’s pH level goes to high or too low then cells do not work– Maintaining pH levels is important for homeostasis– Large changes in pH are controlled by substances called buffers

Examples of buffer in the body’s cells

– Carbonic Acid (H2CO3)

– (H2CO3) → HCO3- + H+

– Carbonic acid dissociates in water to form bicarbonate ion and H ions

Chemical Reactions

Everything that happens in an organism is based on chemical reactions

Definition: a chemical reaction is a process that changes one set of chemicals into another set of chemicals

– Cellular respiration– Formation of Carbonic Acid from carbon dioxide and water

MixtureMixture

2 or more elements or compounds 2 or more elements or compounds that are physically mixed together that are physically mixed together but not chemically combined.but not chemically combined.

Salt & pepperSalt & pepper Earth’s atmosphereEarth’s atmosphere SaladSalad soilsoil

SolutionsSolutionsEvenly distributed Evenly distributed throughout.throughout.Solvent; does the dissolvingSolvent; does the dissolvingSolute; gets dissolvedSolute; gets dissolvedWater is the greatest Water is the greatest solvent.solvent.

Cl-

Water

Cl-

Na+

Water

Na+

NaCI Solution

NaCI Solution

Cl-

Water

Cl-

Na+

Water

Na+

SuspensionSuspension

Unevenly distributed throughout. Unevenly distributed throughout. (settle out)(settle out) Water & gasWater & gas Water & oilWater & oil BloodBlood

4 Organic Compounds

CarbonCompounds

include

that consist of

which contain

that consist of that consist of that consist of

which contain which contain which contain

Carbohydrates Lipids Nucleic acids Proteins

Sugars and starches

Fats and oils Nucleotides Amino Acids

Carbon,hydrogen,

oxygen

Carbon,hydrogen,

oxygen

Carbon,hydrogen,oxygen, nitrogen,

phosphorus

Carbon,hydrogen,oxygen,

nitrogen,

Organic Organic CompoundsCompounds

Organic compounds Organic compounds contains Carbon, Hydrogen contains Carbon, Hydrogen and Oxygenand Oxygen

CarbohydratesCarbohydratesMain source of energyMain source of energyMonosaccharide (simple sugar) Monosaccharide (simple sugar) Glucose – produced by green plants.Glucose – produced by green plants. Fructose – fruits, vegetables, honey.Fructose – fruits, vegetables, honey.

Disaccharides (double sugar)Disaccharides (double sugar) Lactose – mammals milk.Lactose – mammals milk. Sucrose – table sugar.Sucrose – table sugar.

Polysaccharides (complex sugar)Polysaccharides (complex sugar) Cellulose (plants)Cellulose (plants) Starch (plants)Starch (plants) Glycogen (animals)Glycogen (animals)

Glucose

Plants store carbohydrates as Starch

Go to Section:

Animals store carbohydrates as Glycogen in the liver and muscles

LipidsLipids

Stored energyStored energyFatty acidsFatty acidsSaturated fatty acids – meat & dairy.Saturated fatty acids – meat & dairy.Unsaturated fatty acids – plants.Unsaturated fatty acids – plants.PhospholipidsPhospholipidsWaxesWaxesOilsOilsSteroidsSteroids

LipidsLipids

What is it?What is it? Fat, oils, and waxesFat, oils, and waxes Lipid cells together are know as adipose tissue, hey Lipid cells together are know as adipose tissue, hey

look at that spare tire!look at that spare tire!Adipose tissue acts to cushion vital organsAdipose tissue acts to cushion vital organsOnce your body creates a fat cell, it is yours for life, you can Once your body creates a fat cell, it is yours for life, you can never get rid of it!never get rid of it!

FunctionsFunctions Stores a huge amount of energy, even more than that Stores a huge amount of energy, even more than that

carbohydratescarbohydrates But it is used for emergency situations when you run But it is used for emergency situations when you run

out of carbohydratesout of carbohydrates

Types of lipids found in animalsTypes of lipids found in animals

HDLHDL Known as the “good” lipidKnown as the “good” lipid Found in vegetables, oils, and some nutsFound in vegetables, oils, and some nuts Helps clear out LDL of you systemHelps clear out LDL of you system Exercise will increase the levels of HDL in an Exercise will increase the levels of HDL in an

animals systemanimals system

LDLLDLTriglyceridesTriglycerides

ProteinsProteinsMade up of Amino acidsMade up of Amino acids

20 different amino acids20 different amino acids

Structural- Structural- cell, muscle, skin, organs.cell, muscle, skin, organs.

MovementMovement

EnzymesEnzymes

ProteinsProteins

Examples of proteinsExamples of proteins Muscle, insulin, hairMuscle, insulin, hair

FactsFacts Accounts for %50 of cells weightAccounts for %50 of cells weight Used for support, storage, transport defense, Used for support, storage, transport defense,

signaling other cellssignaling other cells Humans have 10s of thousands of different proteinsHumans have 10s of thousands of different proteins Are made of monomers called amino acidsAre made of monomers called amino acids There are 20 different amino acids There are 20 different amino acids

What makes a protein functionWhat makes a protein function The order of the amino acidsThe order of the amino acids

Each protein has a specific orderEach protein has a specific order The shape of a protein determines its functionThe shape of a protein determines its function

Homeostasis: too much acid-proteins unfold. To Homeostasis: too much acid-proteins unfold. To high a temperature: proteins unfold, to cold: high a temperature: proteins unfold, to cold: proteins cant functionproteins cant function

3-D Protein3-D Protein

Nucleic AcidsNucleic Acids

Deoxyribonucleic Acid (DNA)Deoxyribonucleic Acid (DNA)

Ribonucleic Acid (RNA)Ribonucleic Acid (RNA)

Contains genetic informationContains genetic information

Controls the production of proteinsControls the production of proteins

NucleotidesNucleotides PhosphatePhosphate SugarSugar basebase

EnzymesEnzymes

Some reactions that are needed in life are too slow to Some reactions that are needed in life are too slow to happen by themselves.happen by themselves.To speed up these reactions cell in plants and animals To speed up these reactions cell in plants and animals produce catalysts.produce catalysts.

A substance that speeds up chemical reactionsA substance that speeds up chemical reactions They work by lowering the activation energyThey work by lowering the activation energy

Enzymes are proteins that act as biological catalystsEnzymes are proteins that act as biological catalysts Always end in aseAlways end in ase Lactase, carbonic anhydraseLactase, carbonic anhydrase Very specificVery specific

CatalystCatalyst

Substance that reduces the amount of Substance that reduces the amount of energy for a reaction to occur.energy for a reaction to occur.

Catalyst in cells are proteins called Catalyst in cells are proteins called Enzymes.Enzymes.

The substance that the enzyme works on The substance that the enzyme works on are called a substrate.are called a substrate.

Enzymes are very selective.Enzymes are very selective.

Enzyme animationEnzyme animation

http://www.nd.edu/~aostafin/CRCD/DOSS/enzymeanimation3.gif

Reaction pathwaywithout enzyme Activation energy

without enzyme

Activationenergywith enzymeReaction pathway

with enzyme

Reactants

Products

Section 2-4

Effect of Enzymes

Go to Section:

Time to play…

Enzyme lab

Organic compounds lab