what is recation rate in 11 in one marks
Answers
Answer:
explain properly mate......
Answer:
The rate of reaction refers to the speed at which the products are formed from the reactants in a chemical reaction. It gives some insight into the time frame under which a reaction can be completed. For example, the reaction rate of the combustion of cellulose in fire is very high and the reaction is completed in less than a second.
What is Reaction Rate?
The rate of reaction or reaction rate is the speed at which reactants are converted into products. When we talk about chemical reactions, it is a given fact that rate at which they occur varies by a great deal. Some chemical reactions are nearly instantaneous, while others usually take some time to reach the final equilibrium.
This article aims to help students learn about and understand what exactly is the rate of reaction for a given chemical compound.
Explanation:
Rate of Reaction Formula
Let’s take a traditional chemical reaction.
a A + b B → p P + q Q
Capital letters (A&B) denote reactants and the (P&Q) denote products, while small letters (a,b,p,q) denote Stoichiometric coefficients.
As per IUPAC’s Gold Book, the rate of reaction r occurring in a closed system without the formation of reaction intermediates under isochoric conditions is defined as:
Rate of Reaction Formula
Here, the negative sign is used to indicate the decreasing concentration of the reactant.
Average Rate of reaction
Now let us consider the following reaction to understand even more clearly.
A → B
In this reaction a reactant A undergoes a chemical reaction to give a product B. It is a general convention to represent the concentration of any reactant or product as [reactant] or [product]. So the concentration of A can be represented as [A] and that of B as [B]. Let the time at which the reaction begins be the start time, that is t=0.
Let’s consider the following situation:
At t=t1,
The concentration of A=[A]1
The Concentration of B=[B]1
At t=t2,
The concentration of A=[A]2
The concentration of B=[B]2
Now we want to know the rate at which A (reactant) is disappearing and the rate at which the product B is appearing in the time interval between t1 and t2. Therefore,
The rate of Disappearance of A = [A]2–[A]1]t2–t1=–Δ[A]Δt
The negative sign shows that the concentration of A is decreasing.
Similarly,
Rate of disappearance of B = [B]2–[B]1]t2–t1=–Δ[B]Δt
Since A is the only reactant involved in the reaction and B is the only product that is formed and as mass is conserved, the amount of A disappeared in the time interval Δt will be same as the amount of B formed during the same time interval. So we can say that
The rate of reaction = – Rate of disappearance of A = Rate of appearance of B
Therefore, Rate of Reaction = −Δ[A]Δt=Δ[B]Δt
The above terms for the rate of disappearance of A and rate of appearance of B are average rates of reaction. These rates give the rate of reaction for the entire time interval Δt and hence are called average rates of reaction.