What is chemical Equilibrium?

Chemical equilibrium describes the state the a mechanism in which the concentration the the reactant and also the concentration that the commodities do not adjust with time and also the mechanism does no display any kind of further change in properties.

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When the price of the front reaction is equal to the rate of the reverse reaction, the state of chemical equilibrium is accomplished by the system. As soon as there is no further change in the concentrations of the reactants and the assets due to the equal rates of the forward and also reverse reactions, the mechanism is claimed to be in a state the dynamic equilibrium.


Chemical Equilibrium

Types of chemistry Equilibrium

There are two types of chemical equilibrium:

Homogeneous EquilibriumHeterogeneous Equilibrium

Homogenous chemistry Equilibrium

In this type, the reactants and also the products of chemical equilibrium space all in the very same phase. Homogenous equilibrium can be further separated into 2 types: reaction in i m sorry the variety of molecules the the products is equal to the number of molecules of the reactants. For example,

H2 (g) + I2 (g) ⇌ 2HI (g)N2 (g) + O2 (g) ⇌ 2NO (g)

Reactions in i m sorry the number of molecules that the commodities is not equal come the total variety of reactant molecules. Because that example,

2SO2 (g) + O2 (g) ⇌ 2SO3 (g)COCl2 (g) ⇌ CO (g) + Cl2 (g)

Heterogeneous Chemical Equilibrium

In this type, the reactants and also the commodities of chemical equilibrium are current in various phases. A few examples of heterogeneous equilibrium are detailed below.

CO2 (g) + C (s) ⇌ 2CO (g) CaCO3 (s) ⇌ CaO (s) + CO2 (g)

Thus, the different species of chemical equilibrium are based on the phase of the reactants and also products.

⇒ Check: Ionic Equilibrium

Factors Affecting chemical Equilibrium


Change in Pressure:

Change in pressure happens due to the change in the volume. If there is a adjust in push it can affect the gaseous reaction as the total variety of gaseous reactants and also products are currently different. Follow to Le Chatelier’s principle, in heterogeneous chemical equilibrium, the adjust of push in both liquids and solids can be ignored since the volume is elevation of pressure.

Effect of adjust in Volume that Equilibrium Mixture

Change in Temperature:

The result of temperature on chemical equilibrium depends upon the sign of ΔH of the reaction and follows Le-Chatelier’s Principle.

In one endothermic reaction the equilibrium consistent increases with rise in temperature.

Along through the equilibrium constant, the rate of reaction is also affected by the readjust in temperature. Together per Le Chatelier’s principle, the equilibrium shifts towards the reactant side when the temperature rises in instance of exothermic reactions, for endothermic reactions the equilibrium shifts towards the product next with rise in temperature.

Effect of a Catalyst:

A catalyst does not affect the chemical equilibrium. It only speeds up a reaction. In fact, catalyst equally accelerates the forward and also the reverse reaction. This results in the reaction getting to its equilibrium faster.

The exact same amount of reactants and also products will certainly be existing at equilibrium in a catalysed or a non-catalysed reaction. The presence of a catalyst only facilitates the reaction to continue through a lower-energy change state of reaction to products.

Effect of addition of one Inert Gas:

When one inert gas prefer argon is included to a consistent volume the does not take component in the reaction therefore the equilibrium remains undisturbed. If the gas added is a reactant or product affiliated in the reaction then the reaction quotient will change.

Effect of enhancement of Inert Gas

Examples of chemical Equilibrium

In chemistry reactions, reactants are converted into assets by the front reaction and the commodities may be converted into reactants through the backward reaction. The two states, reactants and products are various in composition.

After part time the the begin of the reaction, the price of the forward and also the behind reactions may come to be equal. After ~ this, the number of reactants converted will certainly be formed again by the reverse reaction such the the concentration the reactants and also products do not change anymore. Hence, the reactants and products room in chemistry equilibrium.

N2O4 ⇌ 2NO2PCl5 ⇌ PCl3 +PCl2N2 + H2 ⇌ 2NH3

Importance of chemical Equilibrium

It is useful in numerous industrial procedures like,

Preparation that sulphuric acid by contacts process: In this process, the an essential reaction is the oxidation that sulphur dioxide right into sulphur trioxide. This involves chemical equilibrium.
Equilibrium solved Questions

Problems on chemistry Equilibrium

1. The equilibrium consistent KP for the reaction N2 (g) + 3H2 (g) ⇌ 2NH3 (g) is 1.6 × 10-4 atm-2 at 400oC. What will be the equilibrium consistent of the chemical equilibrium at 500oC if the warm of the reaction in ~ this temperature variety is -25.14 kcal?


Equilibrium constants at different temperature and heat of the reaction are related by the equation,

log KP2 = -25140/2.303 × 2 <773 – 673 / 773 × 673> + log in 1.64 × 10-4

log KP2 = -4.835

KP2 = 1.462 × 10-5 atm-2

2. Offered the equation, N2 (g) + 3H2 (aq) ⇌ 2NH3 (g), Find Q and recognize which direction the reaction will transition in order to reach the state of chemical equilibrium.


Given, = 0.04M,

= 0.09M, and also K = 0.040

Since only nitrogen and also hydrogen concentration is given, it can be assumed as the reactants and ammonia together the product. Due to the fact that ammonia concentration is not given it can be assumed to be zero.

As q is the ratio of the relative concentration of products to reactants, below Q =0.

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Since K = 0.04 is larger than Q, nitrogen and also hydrogen will integrate to type product ammonia.