Chapter 6- Chemical reactivity and mechanisms
Homolytic bond cleavage
generates two uncharged radicals each w one electron. shown with single headed arrows
Heterolytic bond cleavage
generating two charged ions using two headed arrows
Bond dissociation energy (BDE)
the energy required to break a covalent bond by a homolytic bond cleavage
Heat of reaction
total change in enthalpy (∆H°) for the reaction
Exothermic process
system gives energy to the surroundings
∆H° is negative
Endothermic
system recieves energy from the surroundings
∆H° is positive
Enthalpy
used to measure the exchange of energy
Entropy
measure of choas
Rate equation
Rate=k(rate constant)[reactants](concentration of starting materials)
First order
Rate=k[A]
Second order
Rate=k[A][B]
Third order
Rate=k[A]^2[B]
Nucleophile
electron rich
lewis base, can donate a pair of electrons
negative chargepi bonds
Electrophile
electron deficient
lewis acid, can accept electrons
positive charge
carbocations