Equilibrium expressions, writing

We use the definition of the equilibrium expression. Write the products in the numerator and the reactants in the denominator. The exponent for each concentration term is given by the corresponding stoichiometric coefficient fi-om the chemical equation. 

From this equation, we can write the equilibrium expression ... 

Write the equilibrium expression relating the concentrations of reactants and products in reaction (26). Notice that the concentration of water must be included because it is not necessarily large enough to be considered constant. 

Write the equilibrium expression Kc for each of the following reactions ... 

If the mechanism for this equilibrium were given, we could derive an equilibrium expression using the principle of reversibility, but Equation shows that we can write the equilibrium expression directly without knowing details of the mechanism. 

C16-0005. Write the equilibrium expression for the combustion of NH3 during the s Tithesis of nitric acid ... 

Because many species exhibit acid-base properties, it is often possible to write several proton-transfer equilibrium expressions for an aqueous solution. Each such expression is valid if the reactants are species that are actually present in the solution. We have already seen how to focus on the dominant equilibrium consider only those expressions that have major species as reactants, and look for the one with the largest equilibrium constant. 

C18-0073. For the following salts, write a balanced equation showing the solubility equilibrium and write the solubility product expression for each (a) silver chloride (b) barium sulfate (c) iron(H) hydroxide and (d) calcium phosphate. 

C18-0137. The graph shows the titration curve for a solution of formic acid, which is a principal component in the venom of stinging ants. Identify the major species in the solution at equilibrium, identify the dominant equilibrium, and write the equilibrium constant expression for points A, B, C, and D on the curve. 

If you want to prove to yourself that free energies sum, you can write the equilibrium expressions for the first and second reactions and multiply them together, and you ll get the equilibrium expression for the hydrolysis of ATP. Multiplication is equivalent to the addition of logarithms, so that when you multiply equilibrium constants, you re actually adding free energies (or vice versa). 

Note Even though the reverse reaction is favored, we still write the equilibrium expression for the reaction as originally written. This is a major point ... 

A We use the solubility equilibrium to write the Kv expression, which we then solve to obtain the molar solubility, s, of Fe(OH)3. 

SAQ 6.10 The tetra-protic acid H4EDTA (V) has four possible proton equilibrium constants. Write an expression for each, for Ka(1) to Ka(4). 

Step 3 Write an equilibrium expression for the ionization of acetic acid. 

Write the equilibrium expression for each homogeneous reaction. 

Step 2 Write the equilibrium expression. Then substitute the equilibrium molar concentrations into the expression. 

Step 3 Write the equilibrium expression. Substitute the expressions for the equilibrium concentrations into the equilibrium expression. Solve the equilibrium expression for x. 

Write an equilibrium expression that describes the system at equilibrium. 

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