IIT JEE Test Series — Practice smarter, perform stronger.

Chemical Equilibrium formulas

Master Chemical Equilibrium through 22 JEE Advanced-level formulas, systematically structured with every variable spelled out. Revise concept-wise, identify the areas where you need improvement, and focus your preparation with greater precision.

Practise these formulas Know more about IIT JEE

Back to Formula Book

Chemical Equilibrium, every formula

22 formulas, typeset and free. Print it, or keep it open beside your practice.

Equilibrium constant (concentration)
$K_{c} = \frac{[ C ] ^{c} [ D ] ^{d}}{[ A ] ^{a} [ B ] ^{b}}$
Q1MCQKc
For $aA+bB\rightleftharpoons cC+dD$, $K_c$ is:
- A
  $\dfrac{[C]^{c}[D]^{d}}{[A]^{a}[B]^{b}}$
- B
  $\dfrac{[A]^{a}[B]^{b}}{[C]^{c}[D]^{d}}$
- C
  $[C]+[D]$
- D
  $[A][B]$
Equilibrium constant (pressure)
$K_{p} = \frac{p _{C}^{c} p _{D}^{d}}{p _{A}^{a} p _{B}^{b}}$
Q1MCQKp
The equilibrium constant in terms of partial pressures is:
- A
  $\dfrac{p_C^{c}p_D^{d}}{p_A^{a}p_B^{b}}$
- B
  $\dfrac{p_A^{a}p_B^{b}}{p_C^{c}p_D^{d}}$
- C
  $p_C+p_D$
- D
  $p_A p_B$
Kp–Kc relation
$K_{p} = K_{c} (R T)^{Δ n_{g}}$
Q1MCQKp–Kc
The relation between $K_p$ and $K_c$ is:
- A
  $K_p=K_c(RT)^{\Delta n_g}$
- B
  $K_p=K_c RT$
- C
  $K_p=K_c$
- D
  $K_p=\dfrac{K_c}{RT}$
Reaction quotient
$Q = \frac{[ C ] ^{c} [ D ] ^{d}}{[ A ] ^{a} [ B ] ^{b}}$
Q1MCQQ
The reaction quotient $Q$ has the same form as:
- A
  $K$ but with non-equilibrium concentrations
- B
  $\Delta G$
- C
  the rate constant
- D
  the activation energy
Direction of reaction
$Q < K forward, Q > K backward$
Q1MCQDirection
If $Q<K$, the reaction proceeds:
- A
  forward
- B
  backward
- C
  at equilibrium
- D
  stops
Kp in terms of degree of dissociation
$K_{p} = \frac{4 α ^{2}}{1 - α ^{2}} P$
A₂⇌2A
Q1MCQKp and α
For $A_2\rightleftharpoons2A$ at total pressure $P$, $K_p$ is:
- A
  $\dfrac{4\alpha^{2}}{1-\alpha^{2}}P$
- B
  $\dfrac{\alpha^{2}}{1-\alpha}P$
- C
  $\alpha^{2}P$
- D
  $\dfrac{\alpha}{1-\alpha}$
Degree of dissociation (small)
$α = \frac{K _{p}}{P}$
Q1MCQSmall α
For small dissociation, $\alpha$ is approximately:
- A
  $\sqrt{\dfrac{K_p}{P}}$
- B
  $\dfrac{K_p}{P}$
- C
  $K_p P$
- D
  $\dfrac{P}{K_p}$
Free energy and K
$Δ G^{\circ} = - R T ln K$
Q1MCQΔG° and K
The free energy and equilibrium constant relation is:
- A
  $\Delta G^{\circ}=-RT\ln K$
- B
  $\Delta G^{\circ}=RT\ln K$
- C
  $\Delta G^{\circ}=K$
- D
  $\Delta G^{\circ}=-\dfrac{RT}{K}$
van't Hoff equation
$ln \frac{K _{2}}{K _{1}} = - \frac{Δ H}{R} (\frac{1}{T _{2}} - \frac{1}{T _{1}})$
Q1MCQvan't Hoff
The temperature dependence of $K$ is given by:
- A
  the van't Hoff equation
- B
  the Arrhenius equation
- C
  the Nernst equation
- D
  Hess's law
K for reverse reaction
$K_{r e v} = \frac{1}{K _{f w d}}$
Q1MCQReverse K
The equilibrium constant of the reverse reaction is:
- A
  $\dfrac{1}{K_{fwd}}$
- B
  $K_{fwd}$
- C
  $-K_{fwd}$
- D
  $K_{fwd}^{2}$
K for a multiplied reaction
$K^{'} = K^{n}$
reaction multiplied by n
Q1MCQMultiplied reaction
If a reaction is multiplied by $n$, the new equilibrium constant is:
- A
  $K^{n}$
- B
  $nK$
- C
  $\dfrac{K}{n}$
- D
  $K$
K for added reactions
$K = K_{1} \times K_{2}$
Q1MCQAdded reactions
If two reactions are added, the overall $K$ is:
- A
  $K_1\times K_2$
- B
  $K_1+K_2$
- C
  $\dfrac{K_1}{K_2}$
- D
  $K_1-K_2$
Le Chatelier (pressure)
$increase P \Rightarrow shift to fewer gas moles$
Q1MCQLe Chatelier (P)
Increasing the pressure shifts equilibrium toward:
- A
  the side with fewer gas moles
- B
  the side with more gas moles
- C
  neither side
- D
  the solid side
Le Chatelier (temperature)
$increase T \Rightarrow shift in endothermic direction$
Q1MCQLe Chatelier (T)
Increasing the temperature shifts equilibrium in the:
- A
  endothermic direction
- B
  exothermic direction
- C
  forward direction always
- D
  backward direction always
Vapour density and dissociation
$α = \frac{D - d}{( n - 1 ) d}$
Q1MCQVD and dissociation
The degree of dissociation from vapour density is:
- A
  $\dfrac{D-d}{(n-1)d}$
- B
  $\dfrac{D-d}{d}$
- C
  $\dfrac{d}{D}$
- D
  $D-d$
Kc units
$(mol/L)^{Δ n}$
Q1MCQKc units
The units of $K_c$ are:
- A
  $(\text{mol/L})^{\Delta n}$
- B
  mol/L always
- C
  dimensionless always
- D
  L/mol
Equilibrium: rates equal
$rate_{f or w a r d} = rate_{ba c k w a r d}$
Q1MCQRates at equilibrium
At equilibrium, the forward and backward rates are:
- A
  equal
- B
  zero
- C
  maximum
- D
  unequal
Degree of dissociation range
$0 \leq α \leq 1$
Q1MCQα range
The degree of dissociation $\alpha$ ranges from:
- A
  $0$ to $1$
- B
  $-1$ to $1$
- C
  $0$ to $\infty$
- D
  $1$ to $2$
Homogeneous equilibrium
$all species in the same phase$
Q1MCQHomogeneous
A homogeneous equilibrium has all species in:
- A
  the same phase
- B
  different phases
- C
  the solid phase
- D
  the gas phase only
Heterogeneous equilibrium
$pure solids/liquids excluded from K$
Q1MCQHeterogeneous
In a heterogeneous equilibrium, pure solids and liquids are:
- A
  excluded from the equilibrium expression
- B
  included with concentration
- C
  squared
- D
  doubled
Mole fraction & Kx
$K_{p} = K_{x} P^{Δ n_{g}}$
Q1MCQKp and Kx
The relation between $K_p$ and $K_x$ is:
- A
  $K_p=K_x P^{\Delta n_g}$
- B
  $K_p=K_x$
- C
  $K_p=\dfrac{K_x}{P}$
- D
  $K_p=K_x RT$
Effect of catalyst
$K unchanged (equilibrium reached faster)$
Q1MCQCatalyst
Adding a catalyst to an equilibrium:
- A
  does not change $K$
- B
  increases $K$
- C
  decreases $K$
- D
  shifts it forward

More JEE Advanced Chemistry formula sheets

Every chapter sheet is typeset, free and open without a sign-in.

Other ways to revise this chapter

Master this chapter with similar other learning materials.

Preparing students for India’s top institutes

Our students are currently into top technological and medical institutes of India.

IIT Bombay
IIT Delhi
IIT Madras
IIT Kanpur
IIT Kharagpur
IIT Roorkee
IIT Guwahati
IIT BHU Varanasi
AIIMS Delhi
NIT Tiruchirappalli
NIT Rourkela
IIT Bombay
IIT Delhi
IIT Madras
IIT Kanpur
IIT Kharagpur
IIT Roorkee
IIT Guwahati
IIT BHU Varanasi
AIIMS Delhi
NIT Tiruchirappalli
NIT Rourkela

Join QuestPix, Today!

Get notified first, with exam & curriculum updates, course & test series launch offers, motivation & success stories and free learning resources recommended by toppers.

Chemical Equilibrium formulas

Chemical Equilibrium, every formula

Equilibrium constant (concentration)

Equilibrium constant (pressure)

Kp–Kc relation

Reaction quotient

Direction of reaction

Kp in terms of degree of dissociation

Degree of dissociation (small)

Free energy and K

van't Hoff equation

K for reverse reaction

K for a multiplied reaction

K for added reactions

Le Chatelier (pressure)

Le Chatelier (temperature)

Vapour density and dissociation

Kc units

Equilibrium: rates equal

Degree of dissociation range

Homogeneous equilibrium

Heterogeneous equilibrium

Mole fraction & Kx

Effect of catalyst

More JEE Advanced Chemistry formula sheets

Other ways to revise this chapter

Preparing students for India’s top institutes

Join QuestPix, Today!