C 6: T C h he hemistry of Life6.1 - Atoms and T heir Interactions
Section 6.1 Inside This Section...What is an Element?What are Atoms?2 Types of Chemical BondsChemical Reactions
Section 6.1 What is an Element?A substance that can not bebroken down into smallerparticles. 90 elements naturally occur on earth 25 are essential to living things Each element is identified by a symbol
Section 6.1 ElementsC = Carbon Na = Sodium Ca = Calcium
Section 6.1 ElementsK = Potassium Fe = Iron N = Nitrogen
Section 6.1Trace Elements Elements that are present in small amounts in the human body. N,K,Ca, and Fe are a few examples Help control cell metabolism Plants obtain trace elements through their roots while animals obtain trace elements through what they eat.
Section 6.1 What is an Atom?The smallest part of an elementthat still maintains all thecharacteristics of that element.The basic building blocks of allmatter
Section 6.1 What is an Atom?Nucleus: Center of the AtomElectrons: The outer particles Negatively chargedProtons: Particles found in the nucleus Positively chargedNeutrons: Particles found in the nucleus thathave no charge.
Section 6.1 What is an Atom?Electron and Proton numbers are always the same Neutron (0) Electron (-) Proton (+)
Section 6.1 Energy LevelsRegions around the nucleus thatthe electrons travel.Atoms like tohave their outer most energy levelfull.
Section 6.1 Energy Levels & ElectronsEnergy Level # of Electrons 1 2 2 8 3 18
Section 6.1 What are Isotopes?Atoms of the same element that have different numbers of neutrons.
Section 6.1 What are Isotopes?Most carbon nuclei contain six neutronsSome have 7 or 8These three atoms are isotopesWe refer to the isotopes in terms of the combined total ofprotons and neutronsCarbon-12 has 6 protons and 6 neutronsHow many protons and neutrons does carbon-13 and carbon-14 have??
Section 6.1Problem Solving Lab 6.1 Read Problem Solving Lab 6.1 in groups of twos (pg 149) Answer the 4 questions
Section 6.1 CompoundsA substance that is composed of twoor more different elements that arechemically combined.Properties of compounds are differentthan those of their individual elements.(NaCl)Compounds can always be describedwith an equation. (H20)
Section 6.1 Bond #1: Covalent BondsWhen two elements share electrons intheir outer energy level.Atoms are the happiest when theirouter energy level is full.Water is an example
Section 6.1 Bond #2: Ionic BondA bond between atoms that is formed bylosing and gaining an electron. NaCl is an example Na has one electron in its outer shell Cl has 7 in its outer shell The two oppositely charged atoms now attract each other like magnets.
Section 6.1 Chemical ReactionsChemical reactions occur when bondsbetween compounds are broken orformed.Chemical reactions must have the rightenvironment pH Temperature Energy Concentration
Section 6.1 Chemical EquationsReactant + reactant --> ProductReactants undergo chemical reactionsProducts are formed in chemical reactions 2H2 + O2 --> 2H2OKey Point: atoms are never created or destroyed
Section 6.1 MetabolismAll of the chemical reactions thatoccur in the human body. Produce energy Require energy Build necessary molecules for bodily functions
Section 6.1 Solutions and MixturesSolution: A mixture in which Mixture: A combination ofone or more substances are substances in which theevenly distributed in another individual componentssubstance. retain their chemical properties.Sand and Salt Salt Water Kool-Aid
Section 6.1 pH LevelspH is a measure of how acidic or basic a substance is.Scale of 0-14pH paper is used to determine the pH level A pH below 7 is acidic A pH above 7 is basic A pH of 7 is neutral (Water)
Section 6.1 AcidAny substance that formshydrogen ions in water. H+ When HCl is put into water H+ and Cl- ions.
Section 6.1 BaseAny substance that formshydroxide ions in water. OH- When NaOH is put in water you get Na+ and OH- ions.
Section 6.1 Common Acids and BasesAcids Bases Orange Juice Toothpaste Stomach Acids Baking Powder Tomato Juice Chlorine Bleach
Section 6.1 In Review...What is an Element?What are Atoms?2 Types of Chemical BondsChemical Reactions
Section 6.2 Jump StartWhat are somecharacteristics of water?How do organisms usewater to live and grow?
C 6: T C h he hemistry of Life6.2 - Water and Diffusion
Section 6.2 Inside This Section...The Importance of WaterThe Characteristics of WaterBond #3: Hydrogen BondsDiffusion
Section 6.2 The Importance of WaterMost life processes occur onlyin waterHelps to transport materials inorganism70 to 95% of most organisms isWater
Section 6.2 The Characteristics of WaterWater is polarWater sticks but isn’t sticky Capillary action: able to creep up thin tubesWater resists temperature changesWater expands when it freezes
Section 6.2 Water is PolarWater (H2O) contains two hydrogen atoms and one Oxygen atomthat are covalently bonded to each otherThe Shared electrons are more attracted to the Oxygen atomthan to the hydrogen atoms (Unequal sharing)Results in a polar molecule: It has a positive and a negative endPolar likes polar (i.e. Ionic compounds like salt and other polarmolecules like sugar)
Section 6.2 Bond #3: Hydrogen BondsBecause water molecules have a positiveend and a negative end, there will be anattraction between water moleculesThis results in Hydrogen Bonds betweenthe oxygen atom of one molecule andthe hydrogen atom of another Weaker Bond
Section 6.2What Resists Temperature ChangeIt takes a lot of energy to increaseits temperatureLoses a lot of heat when it coolsThese features help maintain asteady environment (i.e. in cells)
Section 6.2Water expands when it freezes Ice Floats - less dense What would happen to lake Michigan if ice was more dense than water?
Section 6.2 Brownian MotionAnything that is moving has kineticenergyIf you look at the molecules ofgasses, liquids and some solidmolecules under a very powerfulmicroscope, you will see that theyare randomly moving --> Brownianmotion
Section 6.2 DiffusionDiffusion: The net movement of particles from an area ofhigher concentration to an area of lower concentration.A very slow process --> Relies on random molecular motion(Brownian motion)Affected by 3 factors Concentration (most important factor) Temperature Pressure
Section 6.2 DiffusionDiffusion continues until the two substances are distributedevenly --> Dynamic EquilibriumConcentration gradient: the difference in concentration of asubstance across space.At dynamic equilibrium, there is no concentration gradient
Section 6.2 In Review...The Importance of WaterThe Characteristics of WaterBond #3: Hydrogen BondsDiffusion
C 6: T C h he hemistry of Life6.3 - Life Substances
Section 6.3 Inside This Section...The Structure of CarbonCarbohydratesLipidsProteinsNucleic Acids
Section 6.3 CarbonCarbon has 4 electrons in its outerenergy levelCan form 4 covalent bonds with other CelementsCan also bond with other carbonatoms
Section 6.3 Carbon3 types of bonds: Single bond: each atom shares 1 electron C Double bond: each atom shares 2 electrons Triple bond: each atom shares 3 electrons
Section 6.3 LipidsLipids are fats and oils.Organic compound with a largeproportion of C-H bonds and lessoxygen than carbohydrates.NonpolarUsed in cells for energy storage,insulation and protection.
Section 6.3 LipidsMost commonly 3 fatty acids bound to a glycerol molecule.(pg 164)
Section 6.3 ProteinsProvide structure for tissues and organsCarry out cell metabolismLarge, complex polymer made of Carbon,hydrogen, oxygen, nitrogen and usuallysulfur.Building blocks are various combinationsof amino acidsAmino acids join together with peptidebond
Section 6.3 ProteinsAn Enzyme is a protein that changes the rate of a chemicalreaction Involved in almost all metabolic processes. Speed up chemical reactions
Section 6.3 Nucleic AcidsStores cellular information in theform of a code.Polymer of smaller subunits callednucleotides.Nucleotides consist of C, H, O, N, Patoms.Nucleotides make up our DNA
Section 6.3 Nucleic AcidsNucleic acids have 3 parts: Nitrogenous A Base Phospha Base te A Simple sugar O O A Phosphate group Sugar
Section 6.3 Nucleic Acids NitrogenousPhospha Base te O O Sugar
Section 6.3 In Review...The Structure of CarbonCarbohydratesLipidsProteinsNucleic Acids