Chapter 2Chapter 2

Chemistry!Chemistry!

MATTER!MATTER!

Everything around you is made of matter.Everything around you is made of matter.

MatterMatter is anything that has mass and is anything that has mass and occupies space.occupies space.

What’s What’s massmass again? again?

Composition of MatterComposition of Matter

ElementsElements are one of the simplest are one of the simplest chemical substances…can’t break chemical substances…can’t break down!down!

90 occur naturally on Earth90 occur naturally on Earth 25 essential to organisms25 essential to organisms

C, H, O, N…C, H, O, N… Trace elementsTrace elements-present in small amounts-present in small amounts

Iron (Fe), Magnesium (Mg), Zinc (Zn)Iron (Fe), Magnesium (Mg), Zinc (Zn)

Periodic TablePeriodic Table

Elements are arranged in the Elements are arranged in the periodic periodic tabletable according to physical and chemical according to physical and chemical characteristicscharacteristics

Atoms: Building BlocksAtoms: Building Blocks

AtomsAtoms are the smallest particles of are the smallest particles of elements that have that element’s elements that have that element’s characteristicscharacteristics

Review of Atomic StructureReview of Atomic Structure NucleusNucleus--

ProtonsProtons- (p+)- (p+)

NeutronsNeutrons- (n0)- (n0)

Electrons and Energy LevelsElectrons and Energy Levels

Electrons form a Electrons form a cloudcloud around nucleus around nucleus Travel in specific regions called energy Travel in specific regions called energy

levels.levels. Levels have limited capacities:Levels have limited capacities:

Level 1-Hold max. of Level 1-Hold max. of 2 e-2 e- Level 2-Hold max. of Level 2-Hold max. of 8 e-8 e- Level 3-Hold max. of Level 3-Hold max. of 18 e-18 e-

Elements are stable when outer level is Elements are stable when outer level is fullfull

Bohr Energy Level DiagramsBohr Energy Level Diagrams

Isotopes of ElementsIsotopes of Elements

IsotopesIsotopes are atoms of the same are atoms of the same element that have different numbers element that have different numbers of neutrons.of neutrons.

Most Carbon contain 6 neutrons….Most Carbon contain 6 neutrons…. Others have 7 and 8…they are isotopes of the Others have 7 and 8…they are isotopes of the

element carbonelement carbon Referred to as C-12, C-13 and C-14Referred to as C-12, C-13 and C-14

Some are unstable-used for Some are unstable-used for radiation radiation therapytherapy

Interactions of MatterInteractions of Matter

A A compoundcompound is a substance that is composed is a substance that is composed of atoms of different elements chemically of atoms of different elements chemically combined.combined.

Chemical reactions happen when atoms are Chemical reactions happen when atoms are rearranged and new rearranged and new bondsbonds are formed are formed

Compounds important to us??Compounds important to us??

BondingBonding

Covalent BondCovalent Bond- two atoms sharing - two atoms sharing electrons to hold togetherelectrons to hold together

Hydrogen StabilityHydrogen Stability

MoleculesMolecules are groups of atoms held are groups of atoms held together by covalent bonds with no chargetogether by covalent bonds with no charge

Molecules are the simplest form of a Molecules are the simplest form of a substance that retains its properties freelysubstance that retains its properties freely

Water MoleculeWater Molecule

Ionic BondsIonic Bonds

An atom that gains or loses electrons has An atom that gains or loses electrons has an electrical charge and is called an an electrical charge and is called an ionion..

Elements will give up/take electrons to fill Elements will give up/take electrons to fill outer shellsouter shells

The attractive force between two opposite The attractive force between two opposite charged ions is an charged ions is an ionic bondionic bond..

Ionic BondsIonic Bonds

Section 2.2- ENERGYSection 2.2- ENERGY

EnergyEnergy is defined as the ability to do work or is defined as the ability to do work or cause change.cause change. NRG can be in various forms and can transfer NRG can be in various forms and can transfer

forms.forms.

Free EnergyFree Energy is the NRG in a system available is the NRG in a system available for work.for work. In cells, it’s the NRG to fuel cell processesIn cells, it’s the NRG to fuel cell processes

NRG can also change states of matter….NRG can also change states of matter….

States of MatterStates of Matter

Atoms in a substance are actually in Atoms in a substance are actually in constant constant motionmotion..

The rate at which atoms or molecules The rate at which atoms or molecules move determines the move determines the statestate..

Three Major StatesThree Major States

SOLIDS:SOLIDS: DEFINITE VOLUMEDEFINITE VOLUME DEFINITE SHAPEDEFINITE SHAPE

LIQUIDS:LIQUIDS: DEFINITE VOLUMEDEFINITE VOLUME NO DEFINITE SHAPE (Containers’ shape)NO DEFINITE SHAPE (Containers’ shape)

GASES:GASES: NO DEFINITE VOLUMENO DEFINITE VOLUME NO DEFINITE SHAPENO DEFINITE SHAPE

NRG & Chemical ReactionsNRG & Chemical Reactions

MetabolismMetabolism is all of the chemical reactions is all of the chemical reactions occurring within an organism.occurring within an organism.

Reactions Reactions break down/build upbreak down/build up molecules molecules important to function.important to function.

Written in chemical equations using Written in chemical equations using symbols and formulassymbols and formulas..

What process is this?What process is this?

Breakdown of RXNsBreakdown of RXNs

ReactantsReactants are on the left side of the are on the left side of the equation. equation.

ProductsProducts are on the right side of the are on the right side of the equation.equation.

Reactant bonds are broken, atoms are Reactant bonds are broken, atoms are rearranged, and new bonds form to make rearranged, and new bonds form to make products!!products!!

Coefficients vs SubscriptsCoefficients vs Subscripts

CoefficientsCoefficients- Big numbers before an - Big numbers before an element or compound.element or compound. Tell you how many Tell you how many moleculesmolecules you have! you have! Ex.- Ex.- 66COCO22 means six means six moleculesmolecules of CO of CO22

SubscriptsSubscripts- Small numbers after an - Small numbers after an element.element. Tell you how many Tell you how many atomsatoms you have! you have! Ex. – HEx. – H22O means 2 O means 2 atomsatoms of H. of H.

NRG TRANSFERNRG TRANSFER

Chemical reactions that involve a net Chemical reactions that involve a net release of NRG are known as release of NRG are known as exergonicexergonic..

Chemical reactions that involve a net Chemical reactions that involve a net absorption of NRG are known as absorption of NRG are known as endergonicendergonic..

CatalystsCatalysts speed up reactions by lowering speed up reactions by lowering the the activation NRGactivation NRG, or NRG needed to , or NRG needed to start the reaction.start the reaction.

Role of Catalyst:Role of Catalyst:

Mixtures vs SolutionsMixtures vs Solutions

A mixture is a combination of substances A mixture is a combination of substances in which they retain their own properties.in which they retain their own properties. Sand & WaterSand & Water

Solutions are mixtures in which one or Solutions are mixtures in which one or more substances distribute evenly in more substances distribute evenly in another substanceanother substance Kool-Aid!!Kool-Aid!!

SolutionsSolutions

SolutesSolutes are the substances dissolved in are the substances dissolved in solutions.solutions.

SolventsSolvents are the substances in which the are the substances in which the solute is dissolved.solute is dissolved.

ConcentrationConcentration is determined by the is determined by the amount of solute dissolved in a fixed amount of solute dissolved in a fixed amount of solution.amount of solution.

If no more solute can be dissolved, the If no more solute can be dissolved, the solution becomes solution becomes saturatedsaturated..

Acids and BasesAcids and Bases

Water molecules can be broken down into Water molecules can be broken down into two oppositely charged ions in a process two oppositely charged ions in a process called called dissociationdissociation..

Acid vs BaseAcid vs Base

pH measures how acidic or alkaline pH measures how acidic or alkaline (basic) a solution is.(basic) a solution is.

Acid is any substance that has more Acid is any substance that has more hydronium ions (Hhydronium ions (H33O+) in water. pH<7O+) in water. pH<7

Base is any substance that has more Base is any substance that has more hydroxide ions (OH-) in water. pH>7hydroxide ions (OH-) in water. pH>7

Acid/Base CharacteristicsAcid/Base Characteristics

ACIDS:ACIDS: Sour TasteSour Taste Can be corrosiveCan be corrosive Examples:Examples:

BASES:BASES: Bitter TasteBitter Taste Feel slipperyFeel slippery Examples:Examples:

Strength of Acids/BasesStrength of Acids/Bases

Strength is based on distance from Strength is based on distance from neutral, or pH of 7.neutral, or pH of 7.

Ex. #1- A base with a pH of 13 is stronger Ex. #1- A base with a pH of 13 is stronger than a base with pH of 8.than a base with pH of 8.

Ex. #2- An acid with a pH of 1 is stronger Ex. #2- An acid with a pH of 1 is stronger than an acid with a pH of 5.than an acid with a pH of 5.

pH ScalepH Scale

pH Scale is based on pH Scale is based on logarithmiclogarithmic scale. scale.

Change in unit equals ten times the Change in unit equals ten times the change in alkalinity or acidity.change in alkalinity or acidity.

Ex.- pH 2 is Ex.- pH 2 is tenten times stronger than pH 3. times stronger than pH 3.

pH ScalepH Scale

BUFFERS!!BUFFERS!!

Living organisms are very sensitive to pH Living organisms are very sensitive to pH changes.changes.

pH in organisms is controlled by pH in organisms is controlled by buffersbuffers

Buffers can Buffers can neutralizeneutralize small amounts of small amounts of acids or bases in a solutionacids or bases in a solution

APE MAN!!APE MAN!!

AATOMIC # = # TOMIC # = # PProtons = # rotons = # EElectronslectrons

Ex- Boron has atomic # 5Ex- Boron has atomic # 5 Boron has 5 protons and 5 electrons!!Boron has 5 protons and 5 electrons!!

MORE APE MAN!!MORE APE MAN!!

MMASS # - ASS # - AATOMIC # = # TOMIC # = # NNeutronseutrons

Ex.- Cobalt has:Ex.- Cobalt has: Mass # = 59Mass # = 59 Atomic # = 27Atomic # = 27 59 – 27 = 32 Neutrons!59 – 27 = 32 Neutrons!

Water’s UniquenessWater’s Uniqueness

1. Water is polar-it has an unequal 1. Water is polar-it has an unequal distribution of charge.distribution of charge. Two Hydrogens=Positive EndTwo Hydrogens=Positive End Oxygen=Negative EndOxygen=Negative End

Molecules attract to each other and to Molecules attract to each other and to ionsions

Ability to dissolve other polar Ability to dissolve other polar substances…substances…

Hydrogen BondingHydrogen Bonding

2. Hydrogen Bonding-the attraction of 2. Hydrogen Bonding-the attraction of opposite charges of H and O.opposite charges of H and O.

Important for holding together large Important for holding together large molecules: Proteins!molecules: Proteins!

Also can occur between hydrogen and Also can occur between hydrogen and most electronegative atom in another most electronegative atom in another polar molecule!polar molecule!

Hydrogen BondsHydrogen Bonds

CohesionCohesion

3. 3. CohesionCohesion is the attraction between is the attraction between particles of the same substance.particles of the same substance.

Creates Creates high surface tensionhigh surface tension Floating organismsFloating organisms Beading on leavesBeading on leaves

How’d he do that?How’d he do that?

AdhesionAdhesion

4. 4. AdhesionAdhesion is the attraction between two is the attraction between two different substances.different substances.

Allows water to creep up thin tubes: Allows water to creep up thin tubes: capillary actioncapillary action

Plants getting water from groundPlants getting water from ground

Specific Heat/VaporizationSpecific Heat/Vaporization

5. Water has a high 5. Water has a high specific heatspecific heat.. Amount of heat NRG needed to raise/lower 1g of Amount of heat NRG needed to raise/lower 1g of

a substance by 1 degree Celsius.a substance by 1 degree Celsius. Takes a lot to go from 0 (freezing) to 100 (boiling)!Takes a lot to go from 0 (freezing) to 100 (boiling)!

Also has high Also has high heat of vaporizationheat of vaporization.. NRG needed to convert 1g of a liquid to gas!NRG needed to convert 1g of a liquid to gas!

Water resists temperature change.Water resists temperature change. Buffer for temperature-limits extremesBuffer for temperature-limits extremes

DensityDensity

6. Water expands when freezing.6. Water expands when freezing. Ice less dense than water!!Ice less dense than water!! Lakes and Ponds…Lakes and Ponds…

What if…..What if…..

Water and Homeostasis?Water and Homeostasis?

What’s that word again?What’s that word again?

How does water help?How does water help?

7.3- Life Substances7.3- Life Substances

Organic molecules contain carbon.Organic molecules contain carbon.

Carbon forms single, double or triple bond.Carbon forms single, double or triple bond.

Organic molecules have great variety…Organic molecules have great variety…

Formulas for compounds may be the Formulas for compounds may be the same but differ in structure- isomerssame but differ in structure- isomers

Also vary in size!Also vary in size! A polymer is a large molecule formed from A polymer is a large molecule formed from

bonding of smaller molecules…usually in bonding of smaller molecules…usually in long chainslong chains

CarbohydratesCarbohydrates

Organic compounds composed of C, H Organic compounds composed of C, H and O.and O.

Monosaccharides-simplest typeMonosaccharides-simplest type

Disaccharides-two monosaccharidesDisaccharides-two monosaccharides

Polysaccharides-many mono. unitsPolysaccharides-many mono. units

PolysaccharidesPolysaccharides

Starch-chains of glucose used as Starch-chains of glucose used as food storage by plantsfood storage by plants

Glycogen-food storage by animalsGlycogen-food storage by animals

Cellulose-cell wall and structural Cellulose-cell wall and structural support for plantssupport for plants

LipidsLipids

Organic compounds with large Organic compounds with large proportion of C-H bondsproportion of C-H bonds

Commonly known as fats and oilsCommonly known as fats and oils Insoluble in waterInsoluble in water Composed of fatty acid chains Composed of fatty acid chains

attached to a glycerolattached to a glycerol Used for energy storage, insulation and Used for energy storage, insulation and

protectionprotection

Saturated vs UnsaturatedSaturated vs Unsaturated

SaturatedSaturated 1. Chains of Carbon single bonded1. Chains of Carbon single bonded 2. Generally solid at room temperature2. Generally solid at room temperature

UnsaturatedUnsaturated 1. Chains of Carbon double bonded1. Chains of Carbon double bonded 2. Generally liquid at room temperature2. Generally liquid at room temperature

ProteinsProteins

Large, complex polymer composed of C, Large, complex polymer composed of C, H, O, N, and sometimes S.H, O, N, and sometimes S.

Building Blocks=Amino AcidsBuilding Blocks=Amino Acids 20 common AA’s20 common AA’s Linked by condensation-removal of -H and Linked by condensation-removal of -H and -OH groups to form water.-OH groups to form water.Resulting covalent bond is called a Resulting covalent bond is called a peptide peptide

bondbond

EnzymesEnzymes

Involved in nearly all metabolic processesInvolved in nearly all metabolic processes

Enzymes are specific proteins that speed Enzymes are specific proteins that speed up chemical reactionsup chemical reactions If there were no enzymes, reactions would not take If there were no enzymes, reactions would not take

place under living conditionsplace under living conditions

Enzymes have active sites for molecules Enzymes have active sites for molecules to bind to and form a productto bind to and form a product

Nucleic AcidsNucleic Acids

Complex macromolecules that store info. Complex macromolecules that store info. in cells in the form of a code.in cells in the form of a code.

Subunits are called Subunits are called nucleotidesnucleotides Consist of C, H, O, N and P atomsConsist of C, H, O, N and P atoms

Nucleotides arranged in 3 groups:Nucleotides arranged in 3 groups: 1. Base1. Base 2. Simple Sugar2. Simple Sugar 3. Phosphate Group3. Phosphate Group

DNA vs RNADNA vs RNA

DNA-Deoxyribonucleic AcidDNA-Deoxyribonucleic Acid Master copy to any organism’s information Master copy to any organism’s information

code.code. Forms the genetic codeForms the genetic code

RNA-Ribonucleic AcidRNA-Ribonucleic Acid Copies DNA for protein synthesisCopies DNA for protein synthesis