chem.redox

• can be extracted from rocks and minerals
• few metals (gold and silver) exist naturally 
• most metals exist as compounds called ores

producing metals from their compounds ex red iron oxide is reduced by CO extract

causes the reduction of a metals compound to an elemental metal 

CO C and H

reactions of substances with oxygen explosive, corrosion, burning

a substance that causes the oxidation of a metal compound

represents what is happening to only one reactant in a n overall reaction -- makes explanations simple

atoms are voncerted to ions and ions are converted into atoms

the gain of electrons 

the loss of electrons

be equal to the total number of electrons lost 

are seperate processes

chem reaction in which leectrons are transferred between particles

apparent net electric charge that an atom would habe if electron pairs in vocalent bonds belonged entirely to the more electreonegative atom 

lose electrons oxidized 

gain electrons reduced

positive of negative number corresponding to the oxidation state assigned to an atom

negative

positive

increase in ioxidation number

decrease in oxidation number 

transfer of valence electrons from one substance to another

• each particle pulls on the same electrons
• if one particle is able to pull electrons away from the other a pontaneous reaction occurs

a susbtance that loses electrons to another 

a substance that gains or removes electrons from another susbstance

a spontaneous redox reaction occurs only if the oxidizing agent (OA) is aboce the reducing agent (RA) in a table of relative strenghts of oxidizing and reducing agents

spontaneous

NONSpontaneous

a device that continusously converts chemical energy into electrical energy

 a group of two or more electric cells connecte in series

a solid electrical conductor there are 2in each cell

an aqueous electrical conductor one in each cell in b/w the two electrodes

positive electrode

negative electrode

device used to measure the energy difference per unit electric charge between two points in an electric circuit

the potential energy difference per unit charge

• the SI unit for electric potential difference 
• 1v =1 j/c

the chemical composition of the reactants in the cell not size

the rate of flow of charge past a point 

greater current

the SI unit for electric current (I)

the SI unit for electric charge and expresses the total charge tranferred by the movement of charged partivles charge (q)

• the reate at which it produces electrical energy 
• measure in watts (W)
• calculated as the product of current and voltate

• measure of energy stored or supplied 
• meaused in j/kg

and electrode and an electrolyte forming half of a complete cell

arrangement of two half cells that can produce electricity spontaneously

the electrode where reduction occurs

the electrode where oxidation occurs

undergoes a reduction at the cathode

undergoes an oxidation at the anode

electrons

from anode to cathode EXTERNALLY

• cathode(+)l electorlyte ll electrolyte l anode (-)
•        reduction                          oxidation

•                             anions-->
•                             <--cations

•  a solid conductor that will not react with any substances present in a cell 
• usually platinum or carbon

2 half shells seperated by a prous boundry with solid electrodes connected by an exernal circuit

the anode

the cathode 

a galvanic cell in which each half cell contains all entities shown in the half reaction equation at SATP conditions with the concentration of 1.o mol/L for the aq entities

the max electric potential difference (voltage) of a cell operating under standard conditions

the ability of a standard half cell to attract electrons in a reduction half reaction

a half cell abritarily assigned an electode potential of exactly zero volts the standard hydrogen half cell 

• E   =    Er     -   Er
• cell   cathode    anode

The solution in a salt bridge must be a “spectator” electrolyte chemically; that is, its ions must not react with the halfcell ions that pass through.