the chemistry of life unit 3 chapter 6. atom proton: positively charged particles neutron: no charge...
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The Chemistry of LifeThe Chemistry of Life
Unit 3Unit 3
Chapter 6Chapter 6
AtomAtom
ProtonProton: positively charged particles: positively charged particlesNeutronNeutron: no charge particles: no charge particlesElectronElectron: negatively charged particles: negatively charged particlesNucleusNucleus: area of the atom where protons : area of the atom where protons and neutrons are foundand neutrons are foundElectron cloudElectron cloud: area of the atom where : area of the atom where electrons are foundelectrons are found
Periodic table of elementsPeriodic table of elements
Element: substance that cannot be broken down to any simpler chemical substance
CompoundCompound
Chemical substance Chemical substance made up or two or made up or two or more atoms of more atoms of different elementsdifferent elements
Must be chemically Must be chemically combinedcombined
Ex: table salt (NaCl)Ex: table salt (NaCl)
Covalent bondCovalent bond: shared electrons : shared electrons between two atomsbetween two atoms
MoleculesMolecules: group of two or more atoms : group of two or more atoms joined covalentlyjoined covalently
How covalent bonds formHow covalent bonds form
Click on image to play video.
Ionic bondIonic bond: transferred electrons : transferred electrons between two atomsbetween two atoms
How ionic bonds are formedHow ionic bonds are formed
Click on image to play video.
Chemical reactionsChemical reactions
Process in which substances undergo Process in which substances undergo changechange
A + B A + B C + D C + D
– A and B are A and B are reactantsreactants.. means means yieldsyields..
– C and D are C and D are productsproducts..
MixtureMixture
combination of substances where the individual combination of substances where the individual substances retain their original characteristicssubstances retain their original characteristics
SolutionSolution
one or more substances (solute) is one or more substances (solute) is distributed evenly throughout another distributed evenly throughout another substance (solvent)substance (solvent)
pHpH
measures the concentration of Hmeasures the concentration of H++ (protons) in a solution(protons) in a solution
Acid vs. BaseAcid vs. Base
AcidAcid: readily forms H: readily forms H++ when in water when in water– pH < 7pH < 7– Ex: stomach juicesEx: stomach juices
BaseBase: readily forms OH: readily forms OH-- when in water when in water– pH > 7pH > 7– Ex: urineEx: urine
NeutralNeutral pH = 7 pH = 7– Ex: bloodEx: blood
Properties of water: cohesionProperties of water: cohesion
PolarityPolarity: unequally shared electrons so : unequally shared electrons so that the molecule has unequal charge that the molecule has unequal charge distributiondistribution– Oxygen pulls on electrons more than Oxygen pulls on electrons more than
hydrogen, where oxygen becomes more hydrogen, where oxygen becomes more negative hydrogen becomes more positivenegative hydrogen becomes more positive
Polar covalent bonds lead to the Polar covalent bonds lead to the cohesioncohesion property of water where water molecules property of water where water molecules are attracted to other water molecules.are attracted to other water molecules.
Cohesion and hydrogen bondsCohesion and hydrogen bonds
Water resists temperature Water resists temperature change.change.
The bonds between oxygen and hydrogen The bonds between oxygen and hydrogen can absorb a large amount of heat energy can absorb a large amount of heat energy before they break.before they break.
Therefore, aqueous environments (ex: Therefore, aqueous environments (ex: lakes, oceans) where there may be great lakes, oceans) where there may be great changes in temperature, organisms can changes in temperature, organisms can still survive.still survive.
Water expands when it freezes.Water expands when it freezes.
Frozen water (ice) is less dense than liquid Frozen water (ice) is less dense than liquid water.water.
Water that is in the cracks of rocks can Water that is in the cracks of rocks can freeze and cause the cracks to become freeze and cause the cracks to become larger. Overtime, the rock erodes.larger. Overtime, the rock erodes.
Water as an ideal solvent.Water as an ideal solvent.
Many substances (solutes) can dissolve in Many substances (solutes) can dissolve in water.water.
Water readily crosses the cell membrane, Water readily crosses the cell membrane, and therefore substances that are soluble and therefore substances that are soluble in water can diffuse more easily.in water can diffuse more easily.
DiffusionDiffusion
The net movement of particles from an The net movement of particles from an area of higher concentration to an area of area of higher concentration to an area of lower concentrationlower concentration
Temperature and pressure can affect the Temperature and pressure can affect the rate (time) of diffusion.rate (time) of diffusion.
Diffusion animationDiffusion animation
PolymersPolymers: molecule made up of : molecule made up of many repeating unitsmany repeating units
“repeating” monkeys
Repeating glucose starch polymeranalogy Ex: glucose monomer bonded to form starch polymer
CarbohydratesCarbohydrates
Carbon, hydrogen, Carbon, hydrogen, and oxygen with a and oxygen with a ratio of Cratio of C1n1nHH2n2nOO1n1n
SEM image of cellulose fibers
LipidsLipids
Fats, oils, waxes, and Fats, oils, waxes, and steroid ringssteroid rings
ProteinsProteins
Carbon, hydrogen, oxygen, and nitrogen Carbon, hydrogen, oxygen, and nitrogen moleculesmolecules
Hemoglobin in red blood cells
Nucleic acidsNucleic acids
DNA, RNA, and ATP DNA, RNA, and ATP energy moleculeenergy molecule
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