CHEM 401 (Exam #1 Definitions)

Reversible Reaction

products can react to form the reactants again

Describe what is happening when a chemical reaction is at dynamic equilibrium

a reversible reaction where the rate of the forward reaction equals the rate of the reverse reaction.

True or false: Reactants and products are present in euwal ammounts hwen a reaction has reached dynamic equlilibrium

False; THey can be dispused unevenly

True or false: Nothins is happening when a systmr is at dynamic equlibrium

False

What does the equlibroum constnat descrive

how far a reversible reaction proceeds before reaching equilibrium

law of mass action

Ratio of products to reactants at equilibrium

Kc vs Kp

Kc uses concentration, Kp uses gas pressure.

ineffective collison

inability to orient corretly as wlel as lack of optimal eneryg

what happens to atokms during a chemcial reaciton

rearrange atoms

transition state

high energy complxwes must go through this for reactants to turn into products

frequency factor

the amount of times a moelucle orients and runs into each other correctly; approach activation barrier

elementary step

moleculartiy

single reaction process (reaction mechansim is a step-by-step sequenc)

number of molecules that come together to react in an elementary step

determining step

slowest elementary step; controls reaction rate

Use the Arrhenius equation to describe why reactions with a high activation energy occur slowly.

Use the Arrhenius equation to describe why reactions usually occur more quickly at higher temperatures

when Ea/Rt is small, this results in a higher activation energy. Making K small.

Increased temp results in increased temp, making e larger, reuslting in a higher rate constnat.