Introduction to acidbase chemistry a chem1 reference text stephen k. Acids and bases are everywhere every liquid you see will probably have either acidic or basic traits. Chemistry 108 chapter 9 lecture notes acids, bases, and equilibrium 3 when an equilibrium constant has a value less than 1, the denominator related to reactant concentration of the equilibrium constant expression is greater than the numerator, which means that at equilibrium the reactants are favored more reactants than products. Feb 18, 2014 068 acidbase equilibrium in this video paul andersen explains how acidbase chemistry can be understood in terms of equilibrium. Weak bases partially react to give ions in aqueous solution e. R p and p r acid dissociation is a reversible reaction. Find materials for this course in the pages linked along the left. Practice predicting the direction of equilibrium for. Acids and bases have a chemical equilibrium in solution. A weak acid equilibrium problem what is the ph of a 0. Nonadditivity of volumes video pdf acids and bases weak acids and bases hydrolysis of salts video pdf dry ice rainbow of colors video pdf battle of the acids video pdf ammonia fountain with bromthymol blue video pdf acidic, basic and neutral salts video pdf acids and bases buffers bet on buffers video pdf.
Water is present in all acidbase chemistry and is amphoteric in. Strong acidsbases dissociate completely, so their equilibrium constants are overwhelmingly large. Water can even react with itself to form acids and bases. Like it or not, sometimes it is just easier to commit really important stuff to memory. Solve for the rice table x by writing the equilibrium expression, plugging in the values from the equilibrium line of the rice table, and setting it equal to the given k a or k b.
Acids and bases chapter 16 applications of aqueous equilibrium chapter 17 thermodynamics. Acid and base equilibrium ionization of water, kw water is amphiprotic meaning it can act as a base or an acid water is capable of selfionization making itself into ions. Proton transfer in biological systems learning objectives 7. Overview of acidbase equilibria questions key the following questions are designed to give you an overview of the topics in acids and bases and equilibria in acidbase solutions. This would be easy to know exactly, except that the ha is not always equal to the concentration of solute that actually went into the solution. That means a equilibrium is established and it lies far. Notes include acidbase definitions, ph calculations for strong acids, strong bases and weak bases, acidbase titration curves and buffer solution calculations. Reactions may still be taking place within the sample, but the forward and reverse reactions are taking place at the same rate, so the concentrations of the products and reactants are not changing with time. Chemistry 108 chapter 9 lecture notes acids, bases, and equilibrium 1 chapter 9 lecture notes. Acids and bases are very common in chemistry and even biology.
It will also help you to become familiar with conjugated acid. The strength of bases strong bases completely dissociate into ions in aqueous solution e. Every arrhenius acid is a bronstedlowry acid and likewise for the bases. Acids and bases weak acid and salt of a strong base. This model, developed by gilbert lewis, defined acids and bases in terms of electronpair transfer. Practice identifying acids and bases using bronstedlowry and lewis definitions. The equilibrium expression for acids is known as the ka the acid dissociation constant. That means a equilibrium is established and it lies far to the left reactant favored. Notice what happens when you get rid of spectator ions for strong acids and bases. For all questions referring to solutions, assume that the solvent is water unless otherwise stated. The equilibrium constant for a strong acid or strong base is undefined, since the reaction the ionization is.
All acids and bases come with a conjugate paira base or acid, respectively, that is formed in conjunction with the original species. The quantity most measured in aqueous acidbase equilibrium is the oxonium hydronium ion concentration but usually called. To find the phpoh, take the logx since x represents the hydronium ion concentration in acids and the hydroxide ion concentration in. Weak acids and weak bases acid base equilibrium weak acids and weak bases do not dissociate completely. Acid and base equilibrium ionization of water, kw water is amphiprotic meaning it can act as a base or an acid water is capable of selfionization making itself into ions this can happen in two ways. Jan 15, 2016 a2 chemistry revision notes on acidbase equilibria. At chemical equilibrium, the products and reactants have reached a state of balance.
Strong acids, weak acids, strong bases, weak bases acids. Strong acids dissociate 100% to ionic form no molecules of acid remain all ions common strong bases know these lioh naoh. Given the equilibrium constant k eq for a reaction, predict whether the reactants or products are predominant. Chemistry 108 chapter 9 lecture notes acids, bases, and equilibrium 3 when an equilibrium constant has a value less than 1, the denominator related to reactant concentration of the equilibrium. Describes the arrhenius, bronstedlowry, and lewis theories of acids and bases, and explains the relationship between them. Although not comprehensive, these few questions do a good job of covering the majority of the concepts and calculations related to this subject area.
Have a good idea of what are strong acids and bases. If stoichiometric amounts are combined, the solution will be slightly basic determine ph of a solution with 0. Strong acids dissociate 100% to ionic form no molecules of acid remain all ions common strong bases know these lioh naoh koh caoh 2 sroh 2 baoh 2 if solvent reduces different reagents to the same strength it is the leveling effect. A solution of calcium hypochlorite, a common additive to. Acids are electron pair acceptors bases are electron pair donors. General chemistrychemical equilibriaacidbase equilibrium. Entropy, free energy and equilibrium please note that the notes are in powerpoint format. Write the formula of the conjugate base for the following compound. Wed like to understand how you use our websites in order to improve them.
Set up the law of mass action hc 2 h 3 o 2 c 2 h 3 o 2. A bronstedlowry base is defined as a substance that can accept a proton. A2 chemistry acidbase equilibria teaching resources. If you know these, you will automatically know if something is a weak acid or base. Practice using curved arrow notation to show the process of acid base reactions bronstedlowry and lewis. An ampholyte is a substance that has the ability to act as either an acid or a base, depending on the other reactant. This tendency is very great, so the reaction in eq 1 is practically complete. We need to be able to identify acids and bases and understand their properties. Acid proton donor lewis acid nonprotic acids chemists use pka values. Explain the difference between weak and strong acids bases and. Hints for working acidbase equilibrium problems there are only six equations needed to solve acid base problems. There are only five possible variables to put into these equations. Lecture 10 the strong acidstrong base equilibrium calculation. The quantitative behaviour of acids and bases in solution can be understood only if their pk a values are known.
Acids and bases react with one another to yield two products. Can assume other acids you encounter are weak if not one of six above. Classification of acids and bases lecture video if you have ever tried to get a stain out of a favorite garment or struggled to clean your bathtub after a long period of neglect, this lecture is for you. Practice writing acidbase reactions and identifying acidbaseconjugate acidconjugate base. Includes the meaning of the term conjugate as applied to acidbase pairs. Acids are named from the latin acidus meaning sour. Computer calculations of acidbase equilibria in aqueous. Monoprotic acidbase equilibria monoprotic acidbase equilibria.
He determined that acids and bases must ionize or dissociate in water. It can be considered an acid in some reactions and a base in others. Define and identify bronstedlowry acids and bases, and identify conjugate acidbase pairs. Water h 2 o can be both an acid and a base, depending on how you look at it. Given a chemical equation, write the law of mass action. This would be easy to know exactly, except that the ha.
An acid dissociation constant, k a, also known as acidity constant, or acidionization constant is a quantitative measure of the strength of an acid in solution. Relate the strength of an acid to the strength of its conjugate base. The ability of acids to react with bases depends on the tendency of hydrogen ions to combine with hydroxide ions to form water. Lewis acids and bases a third definition of acids and bases is the lewis model, which further broadens the range of substances that can be considered acids and bases. Pdf this presentation is useful to familiarize with acidbase equilibria theories. Unlike arrhenius acids and bases, they are not limited to aqueous solutions. Can be used as a teaching resource or selfteaching tool. Strong bases completely dissociate into their ions. Reactions may still be taking place within the sample, but. Use le chateliers principle to explain how a chemical reaction at equilibrium responds when a change is made to the concentration of reactant or.
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