Chemistry of Life: Concept 2 Notes PDF

Chemistry of Life CONCEPT 2 NOTES  Organization of Life ORGANISM ? Matter = POPULATION ORG...

Chemistry of Life CONCEPT 2 NOTES  Organization of Life ORGANISM ? Matter = POPULATION ORGAN SYSTEM anything that has mass and ORGAN occupies space COMMUNITY - Composed of TISSUE B'O SPHER atoms ? The smallest part of an element that still CELL ECOSYSTEM has the properties of that element ? 6 elements CELL ORGANELLES necessary for life = C, H, O, N, P, S MOLECULE ? Cell = most basic BIOME unit of life ATOM  Atomic Structure ? Atoms are made of subatomic particles - Protons (p*) in the nucleus - Neutrons (nº) in the nucleus - Electrons (e) in the surrounding electron cloud + 010 + + 00's Not Rachd. Antenno P e r i o d i c T a b l e o f E l e m e n t s ? Information we can gather from the PT: hydrogen - Element's symbol - Atomic number = number of protons (p*) H 1.0079 ? An atom can be identified by this number ? Also equals the number of electrons (e) in a neutral atom ? Mass Number = number of protons and neutrons Atomic Atomic Protons Neutrons Electrons Mass Symbol Number Number Na 23 33 75  Bonding ? The electron cloud of an atom is divided into energy levels, or shells ? The electrons in the outermost energy level are called valence electrons Al 3p 4n 8p 8n 13p 14n o are Not Rover drience  Bonding ? Group # on the periodic table = how many valence electrons an atom has - Groups = up/down ? Period # on H e 4.00250: the periodic Li Be A t o m i c N u m b e r F Helen 10 N e Symbol 14.00% 10. 1787 table = how 1. 0 0 8 Atomic Mass 15 18 Now Mg Hydrogen A l S i P Cl A r 30 ST376198 32 M Arton m a n y Ca 21 S c C r M n 26 F e C o N i 30 Z n 31 G a Ge A s S e 35 B r 36 K r 10 9111 ? ???. 72.904 83.730 energy R b Sr 391 Y Z r N b M o Tc Ru R h 146 P d A g C d 49 I n 50 S n 51 S b Te 5 3 54 X e 11.14 38.07 1? D HE TIO 121.710 125.60427 JIAN levels an H f Ta W R e 76 O s Ir P t Au H g T I 8 3 P o B5 A t 86 R n La-Lu 118.45 184-307 160.25 182.217 106 MASSS 254.38 338 210 a t o m h a s Fr Ra 3931051 R f 105. D b S g 107 B h 108 H s 109 M t 110 D s R g C n 113 U u t FI 115. U u p 116 L V 117 Uus Uuo 118 Ac-Lr 209. 228 216 200 - P e r i o d s = Lanthanidel Ce Pr N d P m S m Eu G d Tb Series Dy H o EI Tm Yb L u l e f t / r i g h t 95 9a1 100 102 Actinide A c T h ? ? U Np Pu A m C m B k C f E s F m M d N o LI Series trt 33t 8117 231.03018 157 eate thee Bachel Lestea  Bonding ? All atoms want to be stable, which means they need full energy levels of electrons. - Ex. Lithium is in group 1 so it has 1 valence electron. In order to be stable it needs to lose that 1 e. ? When Lithium loses that 1 electron, it is left with 3 protons and 2 electrons. - Is this atom still neutral? - lons are atoms that have a charge.  Bonding ? The lithium ion is written as Lit1 Atomic Atomic Protons Neutrons Electrons Mass Symbol Number Number Li+1 3  Bonding ? They become stable by forming chemical bonds - lonic bonds occur when electrons are transferred from a metal to a nonmetal. ? Ex: NazS, Mg3P2 - Covalent bonds occur when nonmetallic atoms share electrons. ? Ex: H20, COz, NHs ? Covalent bonds are the strongest bonds  Water ? Water (H20) = molecule made of 2 atoms of hydrogen covalently bonded to 1 atom of oxygen - Has special properties, due to the fact that water is a polar molecule  Polar and Nonpolar Molecules ? Polar Molecule: ? Nonpolar Molecule: Unequal sharing of equal sharing of electrons electrons - no - One side is more positive/negative positive regions - One side is more - Does not dissolve in negative water - Dissolves in water - Ex: CO2, 02, lipids - Ex: Water, salt H  W a t e r M o l e c u l e I n t e r a c t i o n s ? Polar water molecules can be attracted to each other ? This attraction = a hydrogen bond ? Covalent bonds hold the water molecule together internally ? Weaker hydrogen Covalent bond bonds hold different water molecules together externally H H Hydrogen bond H  Properties of Water ? Cohesion ? Adhesion ? High specific heat ? Less dense as a solid ? Water is a terrific solvent mid's Net Facest Arience  C o h e s i o n ("co-" means "together") ? The attraction between molecules of the same substance 0 0 0 o - Water sticking to 0 0 0 0 0 ? water ? Causes HIGH surface tension  Adhesion ? Adhesion = The type of attraction that happens between two different molecules - Glass, soil, plant tissue, cotton, etc. ? Forms stronger bonds than cohesion ? Example: - Meniscus forming on graduated cylinder  High specific heat ? The temperature of water does not change easily. ? This helps to regulate cell temperatures in organisms. - Its temperature does NOT fluctuate very much = allows life to live in water  Less dense as a solid ? Solid water (ice) is less dense than liquid water ? it floats in liquid water - Ice floats in water ? Life can exist under frozen surfaces of lakes/seas  Water is a terrific solvent ? Solution - uniform mixture of two or more substances (Lemonade) ? Solute - what gets dissolved (Lemonade powder) ? Solvent - does the dissolving (Water) ? Water's polarity makes it good at dissolving things, nicknamed the "universal solvent"  Hydrophilic and Hydrophobic Substances ? A hydrophilic substance - Has an affinity for water - Water "loving" - Usually dissolves easily in water - Example: salt, sugar ? A hydrophobic substance - Does not have an affinity for water - Water "fearing" - Does NOT dissolve in water - Example: oil