Kinetics

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what is enthalpy?
- also called delta H value
- difference between potential energy of products and potential energy or reactants
endothermic
- absorbs energy
- positive delta H
- products have more energy than reactants
exothermic
- releases energy
- negative delta H
- products have less energy than reactants
what is the function of a catalyst?
- creates an alternate reaction pathway
- lowers first activation energy
- does not affect delta H value
- not used up or changed during a reaction
reversible reactions

reactants are "re formed" from products
non reversible reactions

occur when a solid precipitate occurs or a gas is produced and escapes
what are 2 characteristics of an effective collision? (collision theory)
- proper orientation
- amount of energy
name some factors that affect reaction rate:
- 1) nature of reactants (# of bonds, is it (aq))
- 2) concentration of reactants
- 3) temperature
- 4) surface area
- 5) pressure (gases)
In order for a chemical reaction to occur, there must always be

an effective collision between reacting particles
Which conditions will increase the rate of a chemical reaction?

increased temperature & increased concentration of reactants
what is entropy?
- disorder/randomness
- more disorder = more entropy
- nature tends towards higher entropy
- delta S value
what might lead to higher entropy?
- 1) phase (s to l to aq to g)
- 2) more moles of products than reactants
- 3) products simpler than reactants
- 4) higher temperature = more entropy
free energy (delta G) equation

(Delta H) - (Temperature in K)(Delta S)
a reaction is always spontaneous if (-)...
- delta H is negative (exothermic)
- delta S is positive (more entropy)
a reaction is never spontaneous if (+)...
- delta H is positive (endothermic)
- delta S is negative (losing entropy)
a reaction is spontaneous at high temperatures if (-)...
- delta H is positive (endothermic)
- delta S is positive (more entropy)
a reaction is spontaneous at low temperatures if (+)..
- delta H is negative (exothermic)
- delta S is negative (losing entropy)

Author

katw3

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Kinetics

Description

kinetics unit for NYS regents review 2018

Updated

2018-03-06T05:01:10Z