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Driving reactions to completion. Driving reactions to completion. Completion = 100% yield of product. Cl - (aq) + Ag + (aq) AgCl (s). Cl - (aq) + Ag + (aq) AgCl (s). AgCl precipitates from the solution. Cl - (aq) + Ag + (aq) AgCl (s).
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Driving reactions to completion Completion = 100% yield of product
Cl-(aq) + Ag+(aq) AgCl(s) AgCl precipitates from the solution.
Cl-(aq) + Ag+(aq) AgCl(s) AgCl precipitates from the solution. As the AgCl precipitates, product is removed from solution.
All gases N2 + 3 H2 2 NH3
All gases N2 + 3 H2 2 NH3 exothermic
All gases N2 + 3 H2 2 NH3 exothermic cool
All gases N2 + 3 H2 2 NH3 exothermic cool
N2 + 3 H2 2 NH3 Although a lower temperature favors more NH3 formed, the lower temperature also leads to a very slow reaction.
N2 + 3 H2 2 NH3 An increase in pressure should favor product.
N2 + 3 H2 2 NH3 An increase in pressure should favor product.
N2 + 3 H2 2 NH3 Ultimate solution: react at high Temperature to speed up reaction, cool until NH3 becomes liquid. Remove from reaction vessel and repeat.
C O N C E N T R A T I O N (time)
Heterogeneous equilibrium Involves at least two phases.
Heterogeneous equilibrium Involves at least two phases. What is the concentration of a pure liquid or a pure solid?
Concentrations are not a valid way to define a pure liquid or solid.
Concentrations are not a valid way to define a pure liquid or solid. Moles water = ? Liters solvent
The concentration of a pure liquid or solid is defined as 1.
Law of Mass Action 1. Gases enter equilibrium expressions as partial pressures in atmospheres.
Law of Mass Action 1. Gases enter equilibrium expressions as partial pressures in atmospheres. 2. Dissolved species enter as concentrations in mol L-1.
Law of Mass Action 1. Gases enter equilibrium expressions as partial pressures in atmospheres. 2. Dissolved species enter as concentrations in mol L-1. 3. Pure solids and liquids are represented by 1 at equilibrium , a dilute solvent is 1.
Law of Mass Action 1. Gases enter equilibrium expressions as partial pressures in atmospheres. 2. Dissolved species enter as concentrations in mol L-1. 3. Pure solids and liquids are represented by 1 at equilibrium , a dilute solvent is 1. 4. Partial pressures or concentrations of products appear in the numerator, reactants in the denominator. Each is raised to the power of its coefficient.
The partition coefficient: Materials are soluble to different degrees in different solvents.
The partition coefficient: Materials are soluble to different degrees in different solvents. This allows for a method to separate that material from others.
Solvent a Solvent b Compound x
Solvent a Solvent b Compound x [x]a [x]b
[x]a [x]b Partition coefficient = K = [x]b [x]a
I2 H2O CCl4
I2 H2O and CCl4 are immiscible H2O CCl4
I2(H2O) I2(CCl4) H2O CCl4
I2(H2O) I2(CCl4) [I2]CCl4 K = [I2]H2O H2O CCl4
I2(H2O) I2(CCl4) [I2]CCl4 K = [I2]H2O H2O = 85 Partition coefficient CCl4
Acids and Bases Arrhenius Acids and Bases
Acids and Bases Arrhenius Acids and Bases Acid : increases H+ concentration in water.
Acids and Bases Arrhenius Acids and Bases Acid : increases H+ concentration in water. Base : increases OH- concentration in water.
Acids and Bases Brønsted-Lowrey Acids and Bases
Acids and Bases Brønsted-Lowrey Acids and Bases Acid : substance that can donate H+.
Acids and Bases Brønsted-Lowrey Acids and Bases Acid : substance that can donate H+. Base : substance that can accept H+.
Acids and Bases Brønsted-Lowrey Acids and Bases Acid : substance that can donate H+. Base : substance that can accept H+. Do not require aqueous solutions.
Acids and Bases Brønsted-Lowrey Acids and Bases Conjugate acid-base pairs.
Acids and Bases Brønsted-Lowrey Acids and Bases Conjugate acid-base pairs. Conjugate base: subtract H+ from acid formula.
Acids and Bases Brønsted-Lowrey Acids and Bases Conjugate acid-base pairs. Conjugate base: subtract H+ from acid formula. Conjugate acid: add H+ to the base formula.