Chemical Equilibrium Formulas for NEET 2025 with Factors Affecting it

Chemical Equilibrium Formulas : Chemical equilibrium is a fundamental concept in NEET chemistry, it is an important topic from the NEET 2025 syllabus and refers to the state where the rates of forward and reverse reactions in a chemical system are balanced, resulting in no net change in concentrations over time.

Different Types of Reactions

• Reversible Reactions - A reversible reaction is when the things you started with can turn into new stuff and vice versa. It's like a seesaw - sometimes one side is up, and sometimes the other.
• At some point, they balance out, and you have a mix of both. An example is when a weak acid splits into ions, like vinegar turning into ions of vinegar and hydrogen.
• Irreversible Reactions - An irreversible reaction is like a one-way street. Once you start, you can't easily go back. In NEET chemistry, when substances react and form something new, and it doesn't easily go back to how it was, that's an irreversible reaction.
  • For example, when hydrogen and oxygen make water, you can't easily turn water back into hydrogen and oxygen.

Alternating Current Formula

Chemical Equilibrium Formulas

Law of Chemical Equilibrium or Mass Action

Dynamics of Rigid Bodies Formula

Equilibrium Constant for Partial Pressure

Equilibrium Constant in terms of Mole Fraction

Relation Between Kp and Kc

Kp = Kc (RT) ^Δn

Relation Between Equilibrium Constant and Standard Free Energy

ΔG ^o = – RT ln Keq

(or)

ΔG ^o = – 2.303RT log Keq

This equation relates the standard free energy change (ΔG) to the equilibrium constant (K) at a specific temperature.

NEET Physics Formulas

Reaction Quotient (Q)

Degree of Dissociation

Thermodynamics of Equilibrium

Van’t Hoff Equation =

(or)

NEET Chemistry Formulas

Factors Affecting Chemical Equilibrium

• Concentration of Reactants and Products - Changing the initial concentrations of reactants or products can shift the equilibrium position. An increase in reactant concentration or a decrease in product concentration favors the forward reaction, and vice versa.
• Temperature - Altering the temperature can influence the equilibrium position. For exothermic reactions (release heat), an increase in temperature favors the reverse reaction, while for endothermic reactions (absorb heat), it favors the forward reaction.
• Pressure (for Gaseous Reactions) - Changing the pressure can impact the equilibrium of reactions involving gases. According to Le Chatelier's principle, if the number of moles of gas changes, the system adjusts to counteract the change.
• Catalysts - Catalysts do not change the position of equilibrium but can affect the speed at which equilibrium is achieved. They facilitate both the forward and reverse reactions, reducing the time needed to reach equilibrium.
• Volume (for Gaseous Reactions) - Changes in volume influence equilibrium only for reactions involving gases. If the volume decreases, the system shifts to the side with fewer moles of gas, and vice versa.
• Presence of Inert Gases - Adding inert gases (those that do not participate in the reaction) at constant volume does not affect the equilibrium position. However, if the volume changes, it can alter the concentration of reacting species.
• Nature of Reactants - The type of reaction and the specific chemical species involved can influence equilibrium. Different reactions may respond differently to changes in factors like concentration or temperature.