2nd vs 1st order reactions
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2nd vs 1st order reactions
Could someone give a detailed explanation as to the difference between these two? Confused what order is really standing for, or what a half-life of an order is symbolic of?
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Re: 2nd vs 1st order reactions
A first order reaction has a rate that is proportional to one of the reactant's concentration while the 2nd order reaction has a rate that is proportional to either 2 things of a reactant, if a single reactant's concentration is squared or if there is a product of two reactant's concentrations.
The half life process is an example of the first order reaction, where the proportional rate is consistently decreasing at 1/2 of the current concentration.
The half life process is an example of the first order reaction, where the proportional rate is consistently decreasing at 1/2 of the current concentration.
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Re: 2nd vs 1st order reactions
The rate of first-order reactions depend on the concentration of only one reactant. A second-order reaction corresponds to the square of the concentration of a reactant or the product of the concentration of two reactants.
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Re: 2nd vs 1st order reactions
according to the textbook, a first order reaction is when the rate is proportional to the concentration of the reactant to the power of 1, while the second order's rate is proportional to the concentration to the power of 2
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Re: 2nd vs 1st order reactions
A first order reaction has a rate proportional to the concentration of reactant, whereas the second order reaction has a rate proportional to the concentration squared.
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Re: 2nd vs 1st order reactions
Hi! The textbook says that a reactant's half-life is "the time needed for its concentration to fall to one-half its initial value." As the rate of reaction increases, the half-life decreases because it takes less time for half of the reactants to become their products.
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Re: 2nd vs 1st order reactions
In a first order reaction, doubling the concentration of the reactant doubles the reaction rate. In a second order reaction, doubling the concentration f the reactant quadruples the reaction rate.
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Re: 2nd vs 1st order reactions
Quinton Sprague 1A wrote:Could someone give a detailed explanation as to the difference between these two? Confused what order is really standing for, or what a half-life of an order is symbolic of?
A first order reaction depends solely on one reactant, hence the name "first" relating to one. A second order reaction depends either doubly on a reactant or on two reactants, which also befits the name.
Order essentially just means the amount of parts the reaction is dependent on. First = one part, second = two, and so forth.
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Re: 2nd vs 1st order reactions
The first order reaction has a rate proportional to the [reactants], the second order reaction has a rate proportional to [reactants]^2.
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