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Chemical Equilibrium

Chemical Equilibrium: Constants, Temperature, Concentrations

1. Describe the equilibrium constant in terms of the law of mass action and write equilibrium constant expression for multiple equilibria. 2. Relate the constants and equilibrium constants and describe how equilibrium varies with temperature. 3. Use equilibrium constants to predict the direction of a reaction towards equil

Chemical Reaction - Find unknown mass

A stoppered flask at 25 C contains 250 mL water, 200 mL octanol, and 50 mL of air. An unknown mass of o-xylene is added to the flask and allowed to partition among the phases. After equilibrium has been established, 5.0 mg of o-xylene are measured in the water. What is the total mass (g) of o-xylene present in the flask?

partition of o-xylene among phases..

Could you please explain what formula and step are invovled and please provide (example) if possible A stoppered flask at 25 C contains 250 mL water, 200 mL octanol, and 50 mL of air. An unknown mass of o-xylene is added to the flask and allowed to partition among the phases. After equilibrium has been established, 5.0 mg of

HETP Calculations from Distillations

I am trying to figure out a few questions/problems. -You want a column to have 6 theoretical plates. Your packing material has a HETP value of 1.5. What is the length of the column that you would need? I thought I would multiply the 6 TP by the HETP value. (This was a past quiz question) How do I solve this type of question?

Equilibrium Temperature Calculation

1.) Calculate Ke for the following (equilibrium concentrations given below substances). See attached file for full problem description. 2.) For all three of the equilibria in problem #1 predict (1) how Ke is affected by an increase in temperature, (2) predict how the equilibrium will sh

Haber Process and Solving for Kc

The Haber process for ammonia synthesis is exothermic: N2(g) + 3H2(g) <--(double arrow for equilibrium) --> 2NH3(g) Change in H (degrees) = -92KJ If the equilibrium is constant Kc for this process at 500 Degrees Celsius is 6.0 X 10^-2, what is its value at 300 Degrees Celsius. I am not sure which equation I shou

Equilibrium Concentrations: Example Problem

Problem: Consider the following gas-phase equilibrium reaction: N2(g) + 02(g) <-- (double arrow for equilibrium) --> 2NO(g) Kc = 4.10 X 10 ^-4 at 2000 Degrees Celsius. If 1.0 mol of NO is introduced into a 1.0 L container at 2000 Degrees Celsius, what is the concentration of NO when equilibrium is reached.

Equilibrium constant expressions: Example problems

1. Write the equilibrium constant expression (K) for the following reaction CS2 (g) + 4H2 (g) --> CH4 (g) + 2H2S (g) 2. Write the equilibrium constant expression (K) for the following reaction CuO (s) + H2 (g) --> Cu (s) + H2O (g) 3. Ammonium chloride is sometimes used as a flux in soldering because it decomposes upon he

Equilibrium Concentration of Gas: Example Problem

The equilibrium constant for Kc for the reaction shown is 54.3 at 430 degrees C. H2(g) + I2(g) --> 2 HI(g) At the start if the reaction there are 0.714 moles of H2, 0.984 mole of I2 and 0.886 mole of HI in a 2.00 liter reaction chamber. At equilibrium, what are the concentrations of the gases-

Nitric oxide air polution

The equilibrium constant (Kp) for the formation of the air pollutant nitric oxide (NO) in an automobile engine at 530 degree C is 2.9 x 10 to the minus eleventh N2(g) + O2 (g) = 2 NO (g) What is the partial pressure of NO under these conditions if the partial pressures of nitrogen and oxygen are 3

Calculating PH Concentration

The formation constant for zinc tetraammine ion [ Zn(NH3)4+2] is 4.1 x 108. What is the concentration of free Zn+2 in a solution of 3M NH3 (total ammonia) buffered to a pH of 9.0 if the total zinc concentration is 0.1M? The Kb for NH3 is 1.8 x 10-5

Calculating the concentration of ion at equilibrium

Please help with the following problem. Provide step by step calculations. Consider a solution that is 0.10 M in a weak triprotic acid that is represented by the general formula H3A with the following ionization constants: For H3A: Ka1= 1.0 x 10 ^-3 Ka2= 1.0 x 10 ^-8 Ka3= 1.0 x 10 ^-12 What is the concentration of

Chemical Equilibrium

1. Define dynamic equilibrium state in terms of a) reaction rates b) change in observable properties c) energy and entropy state 2. In which of these closed containers is the vapour pressure the greatest? Explain the choice. a) a 1 L container with 5 mL of water held at 20&#730;C b) a 1 L container with 15 mL of water

Titration of Borax with HCl

1. Would the experimental values of Ksp, (see attachment for formatting); be affected if the samples titrated contained large amounts of solid borax? If so, would the experimental values be falsely high or falsely low? Explain 2. Does the equilibrium constant change as the temperature changes? If so, explain why the equi

Calculate Eqiulibrium Constant

Calculate the value of the equilibrium constant for each of the following reactions ( we abbreviate citric acid as H3Cit) using the Ka values for citric acid and for carbonic acid: H3Cit + HCO3- <--> H2Cit- + H2O +CO2 H3Cit + 3HCO3- <--> Cit3- + 3H2O +3CO2 Given Ka1 of H3Cit =8.4x10-4; Ka2 of H3Cit = 1.8x10-5; Ka3 of H3Ci


I am enclosing a problem is causing me some doubt. As you will read from the problem wording, It seems that the value should be 0.3 mole as well. However, it is not within the options. (See attached file for full problem description) --- When 2.0 mol of carbon disulfide and 4.0 mol of chlorine are placed in a 1.0 Liter fl

The hemoglobin molecule carries oxygen in the blood

Please help answer the following problems. Include references in the solution. The hemoglobin molecule carries O2 in the blood from the lungs to the cells, where the O2 is released for metabolic processes. The molecule can be represented as Hb in its unoxygenated form and as Hb.O2 in its oxygented form. One reason CO is to

Chemistry Calculations and Concepts

Determination of the Molar Mass and Ionization Constant of a Weak Monoprotic Acid Acetic Acid + Water yields Conjugate Base + Hydronium Ion Or HA + H20; H30+ + A- Calculation of the ionization constant for acetic acid from the measured pH of acetic acid samples: Acetic Acid titrated with Sodium Hydroxide and the followin

Calculating Values of Equilibrium Constants

Question states: In the reaction of ammonium chloride (as a solid) dissociating to produce ammonia and hydrogen chloride (both as gases), the equilibrium concentration of each product was found to be 3.71x10^-3 (they each have the same concentration, ammonia is 3.71x10^-3 and hydrogen chloride is 3.71x10^-3). Calculate the v

Chemistry Equilibria Example Problem

Of the following equilibria, only _______ will shift to the left in response to a decrease in volume. a. H2 (g) + CL 2 (g) <-> HCL (g) b. 2SO3 (g) <-> 2SO2 (g) + O2(g) c. Ns (g) = 3H2 (g) <-> 2NH3 (g) d. 4Fe (s) = 3O2 (g) <-> 2Fe2O3 (s) e. 2HI (g) <-> H3(g) + I3 (g)

Equilibrium & Buffers

1. You have a 0.087565 M solution of a weak acid, HA, pH=4.18177. How many grams of NaA (molar mass = 62.476 g/mol) would you have to add to this solution (assume that there is no change in volume) to have a solution with a pH of 7.40000. Would this new solution be a good buffer? Please explain. 2. You have a mixture of

Some Chemistry Problems

A.) For the reaction: 2Cl2 (g) + 2H2O(g) <----> 4HCl(g) + O2 (g), Kp = 6.4 x 10-6 at 500 K. If a fixed volume is filled with initial concentrations of these gases at 227 oC such that [Cl2] = 0.5 M, [H2O] = 0.40 M, [HCl] = 0.5 M, and [O2] = 0.015 M, in which direction will the reaction proceed? b.) 4.00 mol chlotine and 2.00 m

General Chemistry

1. 4CuO(s) + CH4(g) CO2(g) + 4Cu(s) + 2H2O(g) The value of Kc for this reaction is 1.10 at 25.0°C. What is the value of Kp for this reaction? (R = 0.0821 L-atm/K-mol) a. 4.63 b. 26.9 c. 658 d. 37.2 e. 1.52 x 10-3 2. At a certa

Complex ion equilibria

Complex-Ion Equilibria. When sufficient ammonia is added to a 0.00500 M silver nitrate solution to initially give 0.100 M aqueous ammonia, what is the molarity of the silver ion (Ag+) after the complex ion Ag(NH3)2+ has been formed at equilibrium? Ag+(aq) + 2 NH3(aq) = Ag(NH3)2+(aq)

Solubility and common ion effect

Please help with the following problem. Provide a step by step solution. Solubility and the Common-Ion Effect. In problem 1 it was stated that the molar solubility of PbBr2 in pure water is 1.3 x 10-2 M. Calculate the molar solubility of PbBr2 in A) 0.20 M KBr and in B) 0.20 M Pb(NO3)2 Problem 1 in reference is: The Sol

The solubility product constant

The Solubility Product Constant. PbBr2 is a slightly soluble salt. Write A) the chemical equilibrium equation that describes the salt partially dissolving in water and B) the solubility product expression. C) Calculate the Ksp value for lead(II) bromide if the molar solubility in pure water is 1.3 x 10-2 M.

Find: The Equilibrium Constant

The Equilibrium Constant. Question: Consider the reaction 2 NO2Cl(g) = 2 NO2(g) + Cl2(g). A 12.0-L container holds these gases at equilibrium. What is the value of Kc for this reaction if there are 1.036 g NO2Cl, 5.962 g NO2, and 4.578 g Cl2 at equilibrium?

Solubility Ksp calculations

How do you complete a solubility Ksp problem? What is the solubility of aluminum hydroxide in water at 25 degrees Celsius if the Ksp is 3 x 10^-34? What is the concentration of Hydroxide at equilibrium? What is the concentration of a sulfide ion in a 1L solution of cuprous sulfide to which .03mol of cuprous nitrate has be