Respuesta :
This is an incomplete question, here is a complete question.
At a certain temperature, the reaction [tex]2NO(g)+Cl_2(g)\rightarrow 2NOCl(g)[/tex] has an equilibrium constant Kc of 45.0. A chemist creates a mixture with the following initial concentrations: [NO] = 0.10 M, [Cl₂] = 0.20 M, and [NOCl] = 0.30 M. What will happen as the reaction begins?
A. [NOCl] will increase.
B. [NOCl] will decrease.
C. [NOCl] will stay the same.
D. There is not enough information to answer the question.
Answer : The correct option is, (C) [NOCl] will stay the same.
Explanation :
Reaction quotient (Q) : It is defined as the measurement of the relative amounts of products and reactants present during a reaction at a particular time.
The given balanced chemical reaction is,
[tex]2NO(g)+Cl_2(g)\rightarrow 2NOCl(g)[/tex]
The expression for reaction quotient will be :
[tex]Q=\frac{[NOCl]^2}{[NO]^2[Cl_2]}[/tex]
In this expression, only gaseous or aqueous states are includes and pure liquid or solid states are omitted.
Now put all the given values in this expression, we get
[tex]Q=\frac{(0.30)^2}{(0.10)^2\times (0.20)}=45[/tex]
The given equilibrium constant value is, [tex]K_c=45[/tex]
Equilibrium constant : It is defined as the equilibrium constant. It is defined as the ratio of concentration of products to the concentration of reactants.
There are 3 conditions:
When [tex]Q>K_c[/tex] that means product > reactant. So, the reaction is reactant favored.
When [tex]Q<K_c[/tex] that means reactant > product. So, the reaction is product favored.
When [tex]Q=K_c[/tex] that means product = reactant. So, the reaction is in equilibrium.
From the above we conclude that, the [tex]Q=K_c[/tex] that means product = reactant. So, the reaction is in equilibrium that means the concentration of NOCl will stay the same.
Hence, the correct option is, (C) [NOCl] will stay the same.
