Anything that has mass and takes up space

1) oxygen  (O)

2) carbon (C)

3) hydrogen (H)

4) Nitrogen (N)

make up about 96% of body mass

1 protons- positive charge 1 AMU

2 neutrons- no charge 1 AMU

3 electrons- negative charge 0 AMU

atoms that undergo spontaneous decay called radioactivity

the more neutrons in an element the more radioactive it becomes

c12

c14 radioactive

the more neutrons in an element the radioactive unstable it becomes

two or more atoms held together by covalent bounds

two or more different kinds of atoms chemically bonded together

usually ionic bonds

cant be seperated by physical means

all are homogeneous

completely change da physical n chemical prop of an element

two or more components physically intermixed (not chemically bonded)

can be seperated n put together by physical means mostly

can be heterogeneous or homogeneous

no chemical bonding take splace in these

its properties dont change

ex:

suspensions (worst mixed, will settle out)

colloids (best mixed, will not settle out/ larger particles that dont settle out)

solutions (best mixed, cant see the different parts/ soda)

gotta keep shaking up to keep from settling out

heterogenous

particles are very large, settle out and may scatter light

homogeneous mixtures of components that may gases liquids or solids

solute- substance present in the greater amount

solvent- substances present in smaller amounts

made of larger particles that dont settle out

may scatter light

a suspension

is a mixture

chemical bonds

electrons shells

chemical bonds

Valence shell

–an atoms outermost energy level containing chemically active electrons

only electrons here can bond element to element

chemical bond types

ionic (transfer of electrons/metal and nonmetal)

covalent (sharing of electrons/ nonmetal and nonmetal)

hydrogen (weak bond in which hydrogen atom forms a bridge between 2 electron hungry atoms)

a chemical bond between atoms formed by the transfer of one or more electrons from one atom to another

has to be between a metal and a nonmetal

ex: Na⁺Cl^-

have gained one or more electrons.

 have a negative charge

cations

have lost one or more electrons. 

 have a positive charge

sharing or two or more electrons

a nonmetal and nonmetal

Unequal sharing of electrons produces

H₂O

oppposite

non metal and non metal

• Electrons shared equally between atoms produce  
• charge balanced among atoms

carbon dixoide

O=C=O

non metal and nonmetal

the weakest bonds

work cause unequal distrubution of electrons

weak attractive forces

ex: water

occur when chemical bonds are formed, rearranged, or broken

purpose is to make or break bonds

 made up of a reactant ( what we start w/) and a product (what we end up w/)

          HgO  +  Cl2  ®  HgCl  + O2 

             reactants             products

    HgO  +  Cl2  ®  HgCl  + O2

                             reactants             products

§Must be balanced - total # of atoms in reactants and products must be same

when atoms or molecules combine to form a larger, more complex molecules

A  +  B  ®  AB

ex: anabolic - building up

occurs when a molecule is broken down into a smaller molecule  

EX: AB  ®  A  +  B

ex: catabolic - chemical energy released as bonds are broken

one atom displaces (kicks out) the other 

AB  +  C  ®  AC  +  B

two atoms displaces (kicks out) the other

AB  +  DC  ®  AC  +  DB

 are decompostion reactions in that they are the basis of all reactions in which food fuels are broken down for energy

LEO says GER 

reactions that release energy

ex:

1)temperature

2) concentration

3) particle size

4) catalysts

why are many reactions in the body irreversible, while others are reversible?

biochemistry

inorganic compounds

dont contain carbon

ex: water, salts, many acids and bases

CO₂ is the exception. it is an inorganic compound

contain carbon.

are covalently bonded

High heat capacity 

High heat of vaporization 

§Polar Solvent

Reactivity 

Cushioning 

properties of water

High heat capacity

– absorbs/releases large amounts of heat before changing Temperature

properties of water

High heat of vaporization

when water evaporates it changes from a liquid to a gas. this transformation requires large amounts of heat to be absorbed to break the hydrogen bonds that hold water together

ex: sweating 

(universal solvent) 

properties of water

Reactivity

important reactant in many chemical reactions

part of hydrolysis and dehydration synthesis reactions

properties of water

Cushioning

an ionic compound containing cations other than H+ and anions other than hydroxyl ion (OH-) 

inorganic molecule cause no carbon to carbon bond

substances that conduct an electrical current in a solution

alll ions are electrolytes

acids

H+ means lost electrons

Bases

OH- means gain electons

has a metal in front and an OH in the back

disolves lipids 

displacement reaction where mixing an acid and base forms salt and a water

changing the properties of something to make it something else

HCl + NaOH  ® NaCl + H2O

  acid + base ® salt + water

chemical substance or system that minimizes changes in pH by releasing or binding hydrogen ions

weak acids and bases (dont disassociate completely) that resist abrupt and large changes in pH and keep it between 6.5 and 7.5 (blood 7.35---7.45) to control reaction rates

dissassociate quickly.

bases quickly tie up H+

acids can dramatically change the pH of a solution

****  H2CO3  « H+ + HCO3-  ****

eating, breathing, and exercising can change the pH of your blood

organic molecules

monomer

 A molecule that may react chemically to another molecule of the same type to form a larger molecule

linked together by covalent bonds to form polymers

organic molecules

polymer

organic molecules

functional groups

process by which a large molecule is synthesized by removing water and covalently bonding smaller molecules together 

removal of a water molecule to join 2 molecules

addition of water to break a polymer apart by splitting the covalent bond between 2 monomers

breaking a molecule using water

a group of molecules that include sugars, cellulose, and starches 

organic compound formed of carbon, hydrogen and oxygen but proportion of oxygen is lower than carbs

satuaratted is full of Hs. solid @ room temperature

unsaturated has weaker bonds because the bonds are bent.come from plants. liquid @ room temperature

 the major source of stored energy in the body, are compossed of three fatty acid chains  and a glycerol molecule and are found in fat tissue.