What is Chemical equilibrium: Definition and 77 Discussions

In a chemical reaction, chemical equilibrium is the state in which both the reactants and products are present in concentrations which have no further tendency to change with time, so that there is no observable change in the properties of the system. This state results when the forward reaction proceeds at the same rate as the reverse reaction. The reaction rates of the forward and backward reactions are generally not zero, but they are equal. Thus, there are no net changes in the concentrations of the reactants and products. Such a state is known as dynamic equilibrium.

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1. I Equilibrium constant change with stoichiometric doubling (Callen)?

Callen asks us (with respect to an ideal gas) I had thought to proceed as follow. We have the definition for the singular reaction: $$\ln K_s(T) = - \sum_j \nu_j \phi_j(T).$$ Now a reaction which is the sum of this reaction with itself (doubled reaction) has ##\nu_j \to 2\nu_j## so that its...
2. Thermodynamic equilibrium for systems only open to particle exchange

I am only interested in the initial equilibrium conditions, and I am struggling to convince myself whether that should correspond to the equality of chemical potentials for H2 or an equality of temperatures as well. My work is as below: We take both gases as simple ideal (this is only relevant...
3. A question about chemical equilibrium

Hello we learned about the chemical equilibrium and how to write it's formula in the case of liquid and gaseous phase , what about a reaction involving different phases ? like this one : how do we write the formula for the chemical equilibrium ? do we just ignore the carbon ,is there any rules...
4. Chemistry An exercise about chemical equilibrium

Hello i am trying to solve a problem set about chemical equilibrium , the issue is that my results don't correspond to the correction . can someone tell me what is wrong with my answer , thanks here is the problem and his correction : here is my answer :

30. How Does Removing Ammonia Affect Chemical Equilibrium?

Hi, I have simple question N2+3H2 = 2NH3 + heat How would the equilibrium position be affected if ammonia is removed from the vessel?, shouldn't it move to the left to produce more reactants and replace the ammonia? why does it move to the right?, because that's what my texbook says.
31. Chemical equilibrium, getting molarity given pH and Kb

What should be the molarity in an aquatic dissolution for Trimethylamine, ##(CH_3)_3N## if ##pH=11,2##? ##(CH_3)_3N+H_2O \rightleftharpoons (CH_3)_3NH^++OH^-##, ##K_b=6.3 \times 10^{-5}## I know that ##pH+pOH=14 \rightarrow pOH=2.8##, then ##[OH^-]=1.58 \times 10^{-3}## And...
32. Chemical Equilibrium with Multiple Kc

Homework Statement Compound A can react to form B and C according to the following A<->2B Kc=1 A<->C Kc=1 If 1 mole of A is solved into 1 litre of water, what will the concentration of A be after equilibrium has been reached?Homework Equations ICE-tables(?) A<->2B+C Kc=([B]^2[C])/[A] The...
33. Halved volume with chemical equilibrium

Homework Statement The reaction is PCl5 (g) <=> PCl3 (g) + Cl2 In an unknow volume, the following mixture is balanced: 0.14 atm of PCl5 0.36 atm of PCl3 0.50 atm of Cl2 What would be the the pressure of the whole mixture if the volume would be halved? (the answer is 1.88 atm) Homework...
34. Chemistry Calculate Reactant Concentration from Chemical Equilibrium Moles

If someone could check my work on this, I'd appreciate it: Thanks!
35. Chemical Equilibrium: Understanding & Equation

Can someone help me understand the concept of chemcial equilbrium. I think I understand in a certain chemical reaction, know matter the amount of reactants or products, the equilibrium constant will remain approximatly the same. I don't fully understand how the equation to solve for the...
36. Effect of Temperature on Chemical Equilibrium

Hi guys I am a student of AP Chemistry. I am trying to understand the effect of temperature on equilibrium. I know that under the change of temperature, the equilibrium will shift to favor the endothermic process if heat is added and vice versa. But employing the Arrhenius Equation, I see a...
37. Methane Combustion and Chemical Equilibrium

This may belong in the Chemistry section but this is a problem from my Thermodynamics class, so I'll post it here and then move to the Chem section if need be. Homework Statement Methane (CH4) is the principal constituent of natural gas and is often used to represent natural gas. Consider...
38. Calculation of enthelpy and internal energy or air in chemical equilibrium

Homework Statement Consider air in chemical equilibrium at 0.1 atm and T=4500 K. The chemical species are O2, O, N2, N (Ignore NO). Calculate the enthalpy and internal energy per unit mass of the mixture. Neglect electronic excitation in your calculations. K_{p,O_2}=12.19 atm...
39. Chemical Equilibrium and Concentration

The reaction between hydrogen and fluorine has an equilibrium constant of 1.15x102 at a certain temperature. Given the reaction equation H2(g) + F2(g) -> 2HF(g), calculate the equilibrium concentration of HF after 3.00 mol of each component is added to a 1.500 L flask. I attempted solving it...

Hey guys, I have a question regarding the process by which a reaction returns to equilibrium. If a reaction's reaction quotient is greater than its equilibrium constant, it will shift towards the reactants side of the equation to return to equilibrium. How exactly does this happen? Does...
41. Chemical Equilibrium and Probability

I am looking at this equilibrium: H2O + D2O <-> 2DHO (D = Deuterium) I have 2.0 mol of H2O, 1.0 mol of D2O and 2.0 mol of DHO. What are the equilibrium amounts of each of the molecules? What I tried: 6 mol of H, 4 mol of D H2O: P(X=H) & P(Y=H) = 9/25 D2O: P(X=D) & P(Y=D) = 4/25 HDO...
42. Chemical Equilibrium Constant Calculation

Homework Statement If Q = 1.0 1042 for the reaction C(s) + O2(g) → CO2(g) at 25°C, calculate Keq. dGof (Kj/mol) of... C(s)=0 O2(g)=0 CO2(g)=-394.36 Homework Equations dGorxn = -R*T*ln(K)The Attempt at a Solution -394.36*1000 = -8.314472(298)ln(K) K=1.3e69 This is the wrong answer. I'm...
43. Chemical equilibrium concentrations

I have a problem in which It asks to find the equilibrium concentrations but it only give the value of the equilibrium constant and the chemical equation. Is this even possible to solve or does it not have enough information? Here is the problem Determine the equilibrium concentrations...
44. How Is the Equilibrium Constant Calculated for I2 and I- in KI Solution?

Homework Statement A saturated solution of iodine in water contains 0.330g of I2/L. More than this can dissolve in a KI solution because of the following equilibrium- I2(aq) +I-(aq) ------> I3- (aq) where 2 and 3 are subscripts and - is negative charge A 0.1M KI solution actually...
45. How Do You Calculate CO Concentration at Equilibrium in a Gaseous Reaction?

Homework Statement At a certain temperature, the equilibrium constant for the gaseous reaction of CO with O2 to produce CO2 is 5000 lit/mole. Calculate [CO] at equilibrium, if 1 mol each of CO and O2 afre placed in a 2 L vessel and allowed to come to equilibrium. Homework Equations...
46. Concentration of solids and liquids in Chemical Equilibrium

Homework Statement Why don't we take into consideration the concentration of pure solids and pure liquids in equilibrium constant expression? I read that their concentration per unit volume does not change. If the concentrations (moles per litre) don't change then it won't undergo any...
47. Chemical Equilibrium (Need Fast)

Homework Statement 1) Use Le Chatelier's prinicile to explain how a shift in the equilibrium H2CO3(aq) ⇌ H2O(l) + CO2(g) causes a soft drink to go flat when its container is left open to the atmosphere. 2) How might the addition of a noble gas to the reaction vessel affect this equilibrium...
48. Explaining How Temperature Change Affects Chemical Equilibrium

Hey all the people reading this, Just wondering if anyone can explain how a equilibrium system changes with a increase/decrease in temperature occurs. I've been taught that: If my reaction is exothermic i.e. reactants -> products + energy; and i am going to decrease temperature it would be...
49. I with chemical equilibrium problems

[b]1. okay so the equation is: 3A+2B---->C+D K=1.00x10(to the negative third power) A=9.5-M C=0.0200-M D=0.0200 what is B ? [b]3. the answer is either 1.24: 0.0216: : 0.00180 : or 0.110 (i don't remember) so what i don't get is HOW DO I SET UP THE PROBLEM? :confused: go step...
50. Chemical Equilibrium with individual reactions

Homework Statement Homework Equations Kc = (Kp)/ (RT)delta n K_c = (K_a)(K_b) (Where a and b are the individual reactions while c is the overall reaction where the coefficients are the same) The Attempt at a Solution The question prior to this one has individual reactions as...