2vocabulary Atom the most basic and smallest unit of matter Nucleus center of the atomholds protons and neutronsContains subatomic particlescalled protons, electrons and neutronsDiscuss next diagram
3Atoms Nucleus; Protons; + charge; mass = 1AMU Neutrons; no charge; mass = 1AMUElectrons: - charge; no mass
4vocabulary Element specific atoms of one type form pure substances Over 100 elements/pure substances existCa calciumH hydrogenO oxygenNa sodiumC carbon
5Periodic table Elements are organized in a table and assigned a number Number atomic numberTable periodic tableThis your new friend…at least for this next unit!Get use to it
6Atomic Number Defines the element Is equal to the number of protons Is equal to the number of electrons in a neutral atomAlways the whole number
7C 6 Carbon 12.011 Atomic Mass Atomic Number An Element in the Periodic TableSection 2-1Atomic Number6CCarbon12.011Atomic MassGo to Section:
9Atomic MassIs equal to the number of protons and neutrons in the nucleus of the atomMay not be a whole number on the periodic tableIn biology you may round up the mass number to a whole number
10To find the number of Neutrons Atomic mass – atomic number = Neutrons
11Isotopes of CarbonNonradioactive carbon-12Nonradioactive carbon-13Radioactive carbon-146 electrons6 protons6 neutrons6 electrons6 protons7 neutrons6 electrons6 protons8 neutronsIsotopes have the same number of protons and electrons but have a different number of neutrons
21How are things kept together Ionic BondsTransferring of electronsCreate ionsOpposite charged particles are attracted to each otherElectrons are gained/lostCovalent bondsCan create slightly different chargesStrongest chemical bondOrbitals/shells overlap and electrons bounce back and forthVan der Waals forcesHappens when molecules are super close togetherHydrogen bonding-weak bonds
22Drawing molecules showing Ionic Bonding Draw all atoms showing protons, and electrons in their energy levelsDecide which electrons must be transferred in order to fill all of the atoms outer levelDraw the electrons being transferredShow the resulting charge on the Ions
23Ionic Bonding Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+) Chloride ion (Cl-)Transferof electronProtons +11Electrons -11ChargeProtons +17Electrons -17ChargeProtons +11Electrons -10ChargeProtons +17Electrons -18Charge
24Ionic Bonding Sodium atom (Na) Chlorine atom (Cl) Sodium ion (Na+) Section 2-1Sodium atom (Na)Chlorine atom (Cl)Sodium ion (Na+)Chloride ion (Cl-)Transferof electronProtons +11Electrons -11ChargeProtons +17Electrons -17ChargeProtons +11Electrons -10ChargeProtons +17Electrons -18Charge
25Draw the following molecules showing them form ionic bonds KFMgCl2
27Covalent Bonding Sharing of electrons No ions are formed Sharing of electrons holds it together.
28Guided/independent practice Chemistry worksheet…time to think!
29Water Most abundant compound found in living things. Water is a molecule (H2O)Water is a polar molecule. (unequal sharing of electrons)Hand out chemistry worksheet!
30Water Facts It is a neutral molecule Water is the single most abundant compound on earthIt expands when it freezesIt floats when frozenWhat advantage does this play in the survival of fish and plants75% of earth is waterThe human body is 70% waterPh of 7.0
31Properties of Water Its Polar High heat capacity It has a negative end and a positive endUneven sharing of electronsHigh heat capacityAbsorb
32Hydrogen bondsBecause of the uneven charge water atoms can attract each otherCohesion: attraction between molecules of the same substanceInsects walking on waterAdhesion: attraction between molecules of different substancesWater drawn up a plant (capillary action)
35Acids, Bases, and the pH scale Water is the universal solventMost compounds will dissolve in waterRemember 75% of most animals are waterH20 → H+ + OH-Water → Hydrogen ion + Hydroxide ionOnly about one water molecule in 55 million will form a hydrogen ionH+ = OH- , so water is always neutral
36PH scale – measures the concentration of H+ and OH- ions. Ranges from 0-14At 7 the concentration of H+ and OH- is equal. (pure water)Acid – H+ ions, 0-6Alkaline or base- OH- ions, 8-14Each step represents a factor of 10
41BuffersFactsMost cells in animals must generally be kept at a pH level between 6.5 and 7.5Human blood has a pH of 7.4If the body’s pH level goes to high or too low then cells do not workMaintaining pH levels is important for homeostasisLarge changes in pH are controlled by substances called buffers
42Examples 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
43Chemical ReactionsEverything that happens in an organism is based on chemical reactionsDefinition: a chemical reaction is a process that changes one set of chemicals into another set of chemicalsCellular respirationFormation of Carbonic Acid from carbon dioxide and water
44Mixture2 or more elements or compounds that are physically mixed together but not chemically combined.Salt & pepperEarth’s atmosphereSaladsoil
45Solutions Evenly distributed throughout. Solvent; does the dissolving Solute; gets dissolvedWater is the greatest solvent.
56Lipids What is it? Functions Fat, oils, and waxes Lipid cells together are know as adipose tissue, hey look at that spare tire!Adipose tissue acts to cushion vital organsOnce your body creates a fat cell, it is yours for life, you can never get rid of it!FunctionsStores a huge amount of energy, even more than that carbohydratesBut it is used for emergency situations when you run out of carbohydrates
57Types of lipids found in animals HDLKnown as the “good” lipidFound in vegetables, oils, and some nutsHelps clear out LDL of you systemExercise will increase the levels of HDL in an animals systemLDLTriglycerides
58Proteins Made up of Amino acids 20 different amino acids Structural- cell, muscle, skin, organs.MovementEnzymes
59Proteins Examples of proteins Facts Muscle, insulin, hair Accounts for %50 of cells weightUsed for support, storage, transport defense, signaling other cellsHumans have 10s of thousands of different proteinsAre made of monomers called amino acidsThere are 20 different amino acids
60What makes a protein function The order of the amino acidsEach protein has a specific orderThe shape of a protein determines its functionHomeostasis: too much acid-proteins unfold. To high a temperature: proteins unfold, to cold: proteins cant function
71EnzymesSome reactions that are needed in life are too slow to happen by themselves.To speed up these reactions cell in plants and animals produce catalysts.A substance that speeds up chemical reactionsThey work by lowering the activation energyEnzymes are proteins that act as biological catalystsAlways end in aseLactase, carbonic anhydraseVery specific
72CatalystSubstance that reduces the amount of energy for a reaction to occur.Catalyst in cells are proteins called Enzymes.The substance that the enzyme works on are called a substrate.Enzymes are very selective.
74Effect of Enzymes Reaction pathway without enzyme Activation energy Section 2-4Reaction pathwaywithout enzymeActivation energywithout enzymeReactantsActivationenergywith enzymeReaction pathwaywith enzymeProductsGo to Section: