the area of chemistry concerned with reaction rates and the sequence of steps by which reactions occur
To describe a reaction rate, we must specify __. What is the rate?
how fast the concentration of a reactant or a product changes per unit time
rate= concentration change/ time change
reaction rate
either the increase in the concentration of a product per unit time or as the decresae in the concentration of a reactant per unit time
rate=delta[x]/ deltat
What are units for rates
Molar per second M/s
Why do we define reaction rate in terms of concentration (moles per liter) rather than moles?
because we want the rate to be independent of the scale of the reaction
The steeper the slope of the hypotenuse, the __
faster the rate
Reaction rate is defined as a __
positive quantity
The general rate of a reaciton equals
the rate of consumption of a reactant or formation of a product divided by its coefficient in the balanced chem equation
The slope of the tangent to a concentration-versus-time curve at a time t is called the __ at that particular time. The instantaneous rate at the beginning of a rate (t=0) is called the __.
instantaneous rate
initial rate
what is the rate law?
rate= - delta[A]/ deltat= k[A]^m[B]^n
What does an exponent of one indicate?
the rate depends linearly on the concentration of the corresponding reactant
What does m=0 mean?
the rate is independent of the concentration of A because any number raised to the zeroth power equals one
If m is negative, __
the rate decreases as [A] increases
The values of the exponents m and n determine the __ with respect to A and B, respectively. The sum of teh exponents (m+n) defines the __.
reaction order
overall reaction order
The values of the exponents in a rate law must be determined by __; they cannot be deduced from the __ of the reaction.
experiment
stoichiometry
One method of determining the values of the exponents in a rate law--the __--is to carry out a series of experiments in which the initial rate of a reaction is measured as a function of different sets of initial concentrations.
method of initial rates
first order reaction
one whose rate depends on the concentration of a single reactant raised to the first power
What is the integrated rate law?
ln[A]t/[A]0= -kt
[A]0 is initial time concentration
A graph of ln [A] versus time is a __ having a slope of __. The value of hte rate constant is simply equal to __.
straight line
m=-k
-(Slope)
First order reaction graphs?
the exponential decay is the same for every interval