U1: CH2 EVERYTHING

chemical level

first level of organization in human body

matter

anything that takes up space and has mass

mass

weight, the quantity of material in matter

atoms

smallest stable units of matter, composed of subatomic particles

subatomic particles of atom

protons, neutrons, electrons

protons (p+)

have positive electrical charge, in nucleus

neutrons (n)

have neutral/no charge, in nucleus

electrons (e-)

have negative electrical charge, much smaller than protons or neutrons, exist in electron cloud outside of nucleus

atoms and elements

normally contain equal numbers of protons and electrons

atomic number

total number of protons in an atom

mass number

total number of protons and neutrons in an atom

element

substance composed only of atoms with same atomic number (ex: hydrogen)

atomic mass

actual mass of an atom of a specific isotope

atomic weight

equals average mass of an element, including different isotopes in proportion

isotopes

same of an element but different atomic mass, atoms with same number of protons but different numbers, identical chemical properties, different mass number (tells number of subatomic nuclei)

why are atoms are electrically neutral

every positive proton is balanced by a negative electron and electrons occupy an orderly series of energy levels within the electron cloud

valence shell energy level

outermost energy level of atoms surface

reactive energy level

atoms with unfilled outer shell, tends to react with other atoms to fill outer shell

inert energy level

atoms with full outer shells, does not readily react with other atoms, more stable, (ex: noble gases)

losing an electron

fewer electrons (negative) than protons (positive, net positive charge, called “positive ion”/”cation,” one missing electron=charge of+1, more electrons missing=more positive charge

gaining an electron

more electrons (negative) than protons (positive), net negative charge, called “negative ion”/”anion,” one extra electron=charge of -1, more electrons gained=more negative charge, stabilizing interactions often form chemical bonds

what does chemical bonding create

compounds and molecules

compounds

chemical substance made up of atoms of two or more different elements in a fixed proportion, regardless of type of bond joining them

molecules

chemical structure consisting of atoms of one or more elements held together by covalent bonds

forming ionic compounds

1. losing and gaining electrons

2. becoming ions (cations and anions)

3. charges attract which forms ionic bond

4. formation of crystals often occur

covalent bonds

sharing electrons between atoms, forms molecules, single covalent bond or double covalent bond

nonpolar molecule

formed by typical covalent bond, electrons equally shared between atoms, no electrical charge on molecule

polar molecule

composed of polar covalent bonds, unequal sharing of electrons between atoms, (ex: water molecule)

3 states of matter

solid, liquid, gas

solid

maintains volume and shape at ordinary temperatures and pressures

liquid

as constant volume, shape determined by container

gas

independent particles, hass neither a constant volume nor fixed shape, can be compressed or expanded, will fill a container of any size

water

only substance that exists in all three states of matter at temperatures compatible with life (solid=ice, liquid=water, gas=water vapor)

hydrogen bond

attraction of the small positive charges on hydrogen atoms (of a polar molecule) to negative charges on atoms in other polar molecules, can change shape of molecules or pull molecules together

effects of h bonds on water properties

constantly forming and breaking in liquid state, locked when frozen (accounts for expansion), water vapor when all H bonds broken, slows rate of evaporation, responsible for surface tension (acts as a barrier keeping small objects from entering the water), water as a solvent (polar changes on water disrupt ionic bonds (dissolve) a variety of inorganic compounds)

each cell is what

chemical factory that produces essential functions like providing energy, maintenance and repair, growth, cell division, secretion, and contraction

metabolism

all reactions in the body at any moment (catabolism and anabolism)

reactants

participants at reaction start, usually on the left

products

generally at end of reaction, usually on right

chemical notation for ions

subscript plus or minus following symbol indicates an ion. Ex: cation with +1=atom has lost one electron, anion with -1: atom gained one electron, numberbefore sign indicates more than one electron lost or gained -2/+2

decomposition reactions

break a molecule into smaller fragments, occur inside and outside of cells (ex:digestion of food for absorption)

hyrolysis

specific type of decomposition reaction, requires water to break bonds

catabolism

collective term for decomposition reactions in the body,break covalent bonds (form of potential energy), release kinetic energy that can perform work, body can use energy for growth, movement, and reproduction

synthesis reactions

assemble smaller moleculesinto larger molecules, alwayse involve formation of new chemical bonds

dehydration synthesis

condensation, formation of a complex molecule by removing/releasing a water molecule, opposite of hydrolysis

anabolism

anabole=throwing upward, collective term for synthesis reactions, refers to forming new chemical bonds, requires energy usually from other catabolic reactions

decomposition and synthesis reactions are often

coupled together

equilibrium

rates of both reactions are in balance

most chemical reactions require what to activate reactants

activation energy, minimum energy required to activate reactants in a reaction and allowreactionto proceed, outside the body, may be acquired by extremes in temp, pressure, or lethal chemical factors

enzymes

special proteins used by cells inside the body, promote chemical reactions, lower the required activation energy, catalysts, reactions continue until equilibrium is reached, reactions may absorb or release energy

exergonic reaction

exo=outside, overall net release of energy, common in the body and help to maintain body temperature

endergonic

endo=inside, more energy is required to begin than is released, include reactions to build molecules

metabolites

metabole=change, substances synthesized or decomposed by enzymatic reactions

nutrients

essential metabolites that are normally obtained from our diet

macromolecule

large molecule made up of monomer subunits

monomer

molecule that can be bonded to other identical molecules to form a polymer, repeating monomers join through dehydration synthesis to form polymers

hydrolysis

reactions separate polymers to form monomers

bodies are 2/3 water

lubrication, chemical reactant, high heat capacity (temp is relatively stable), excellent solvent

ionization/dissociation

process of breaking ionic bonds as ions interact with poles of a water molecule, in aqueous solution anions (-) surrounded by positive poles of water, cations (+) surrounded by negative poles of water, hydration spheres

hydration spheres

a layer of water molecules around an ion

molecules with polar covalent bonds attract water molecules

water forms hydration sphere around the molecule, if the molecule bonds to water strongly, it will dissolve (hydrophilic=water loving), molecules that interact with water readily, ex:glucose

aqueous solution with anions and cations will conduct eletrical current with what

electrolytes, cations, ions

electrolytes

soluble inorganic substances whose ions will conduct electrical current, e

in electrical field

cations move toward negative terminal, anions move toward positive terminal