The answer to this question depends on what you mean by “reaction rate.” In general a reaction rate is the speed at which a chemical reaction takes place. The units of reaction rate are usually given as mol/L/s which stands for moles of reactant per liter of solution per second. However there are a variety of other ways to measures reaction rates such as the rate of change of the concentration of a reactant or product over time or the rate of change of the pressure of a reactant or product over time.
There are a number of factors that can affect the rate of a chemical reaction. The most important factor is the nature of the reactants. Reactants that are more chemically reactive will tend to have a higher reaction rate than reactants that are less chemically reactive. The second important factor is the temperature of the reactants. In general as the temperature of the reactants increases the reaction rate will also increase. The third important factor is the concentration of the reactants. Generally speaking the higher the concentration of the reactants the higher the reaction rate.
There are a number of ways to increase the reaction rate of a chemical reaction. One way is to increase the temperature of the reactants. This will generally increase the kinetic energy of the particles which will in turn increase the chance of a collision between reactant molecules. Another way to increase the reaction rate is to increase the concentration of the reactants. This will increase the number of molecules that are able to collide which will again increase the chance of a reaction taking place.
In general the expression that best represents a reaction rate is the rate of change of the concentration of a reactant or product over time. However as mentioned above there are a variety of ways to measure reaction rates and so the best expression to use will depend on the particular reaction being considered.
References:
“Reaction Rate.” Chemistry LibreTexts. LibreTexts 21 Mar. 2020. Web. 23 Mar. 2020.
“Factors That Affect Reaction Rates.” Chemistry LibreTexts. LibreTexts 21 Mar. 2020. Web. 23 Mar. 2020.
“How to Increase Reaction Rates.” Chemistry LibreTexts. LibreTexts 21 Mar. 2020. Web. 23 Mar. 2020.
What is the expression for the rate of a reaction?
The rate of a reaction is the change in concentration of a reactant or product per unit time.
What is the expression for the rate of a first-order reaction?
The rate of a first-order reaction is the change in concentration of a reactant or product per unit time.
What is the expression for the rate of a second-order reaction?
The rate of a second-order reaction is the change in concentration of a reactant or product per unit time squared.
What is the expression for the rate of a zero-order reaction?
The rate of a zero-order reaction is the change in concentration of a reactant or product per unit time.
What is the expression for the rate of a reaction that is not first order or second order?
The rate of a reaction that is not first order or second order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not zero order?
The rate of a reaction that is not zero order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not first order?
The rate of a reaction that is not first order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not second order?
The rate of a reaction that is not second order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not zero order or first order?
The rate of a reaction that is not zero order or first order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not zero order or second order?
The rate of a reaction that is not zero order or second order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not first order or second order?
The rate of a reaction that is not first order or second order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not zero order first order or second order?
The rate of a reaction that is not zero order first order or second order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not zero order first order second order or third order?
The rate of a reaction that is not zero order first order second order or third order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not first order second order or third order?
The rate of a reaction that is not first order second order or third order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
What is the expression for the rate of a reaction that is not second order or third order?
The rate of a reaction that is not second order or third order is the change in concentration of a reactant or product per unit time to the power of the order of the reaction.
