Acids and Bases

Acids and BasesStrong Acids, strong bases and pH

Bronsted-Lowry Model of Acids and BasesAcid is a proton donor, base is a proton acceptor.

HB(aq) + A-(aq) HA(aq) + B-(aq)

HA and HB are acids, A- and B- are basesHB & B- and HA & A- are conjugate acid-base pairs.

Watch this animationhttp://www.mhhe.com/physsci/chemistry/essentialchemistry/flash/acid13.swf

Watch this animation about acids and bases in solutionhttp://preparatorychemistry.com/Bishop_Neut_frames.htm

Watch the acid animation at the same site look at the menu on the left

Demo - A Voice Activated ReactionAcidic and Basic Water Solutions

In any aqueous solution, there is an equilibrium between H3O+ (H+) ions and OH- ions.2 H2O H3O+(aq) + OH-(aq)

Kw = [H3O+][OH-] = 1.0 x 10-14 @25oC

So in pure water: [H+] = [OH-] = 1.0 x 10-7 MA neutral solutionAcidic solutions: [H+] > 1.0 x 10-7 M > [OH-]Basic solutions: [OH-] > 1.0 x 10-7 M > [H+]

ExIn sea water, [H+] = 5 x 10-9 M[OH-] = ?

pH Scale

pH = -log[H+]neutral solution: pH = 7.0acidic solution: pH < 7.0basic solution: pH > 7.0Look at the animation at: http://www.johnkyrk.com/pH.html

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ex Suppose [H+] = 2.4 x 10-6 M; calculate pH

Ex Suppose pH = 8.68; Calculate [H3O+]

pOH = -log[OH-]

[H+][OH-] = 1 x 10-14

pH + pOH = 14

Watch the music videohttp://www.youtube.com/watch?v=u9nOIZDdvRw

Here is the notes quizhttps://docs.google.com/spreadsheet/embeddedform?formkey=dGhuNE53RkdkV1ZJc1BGdGFQeEEzVWc6MQ