Acids Bases I Properties of Acids Bases acids

Acids & Bases I. Properties of Acids & Bases -_____ acids taste ____ sour and produce a _______ burning sensation to the touch citric acid and ____ ascorbic acid, -______ (also known as _______ Vitamin __), C are weak _____ acids responsible for the _____ tartness of ______ citrus and other _______ fruits while ______ acetic ____ acid makes ______, vinegar taste ____, sour and in our body, _______ the unpleasant ____ sourness and Hydrangea – the color varies depending on the relative acidity or basicity of the soil burning _____ sensation produced by _______ vomit is due to ______ hydrochloric our _____ acid in our ____ stomach ____

Acids & Bases I. Properties of Acids & Bases -because _____ acids ____ burn and _______ denature ____, proteins (and all ______ living ______ things are made of _______), proteins in ______, nature defense they are often used as a _______ -____, bees ____, ants ______, nettles and ______ onions formic ____ acid to ______ defend all use ______ themselves, while the human stomach bacteria _______ is guarded against _______ by ______ hydrochloric ____, acid the human ______ is guarded against _______ vagina bacteria lactic ____ acid (produced by by ______ sugar _____ fermenting _______ bacteria of the _____genus Lactobacillus ______), and even human ____ skin is guarded by ____ uric ____ acid in our _____ sweat Stinging Nettle

Acids & Bases I. Properties of Acids & Bases -_____ acids react with ______, metals especially the more ______ active ______, metals to produce ____ ___ hydrogen gas 1 Zn (s) + 2 HCl (aq) 2 Al (s) + 6 HNO 3 (aq) 1 Zn. Cl 2 (aq) + 1 H 2 (g) 2 Al(NO 3)3 (aq) + 3 H 2 (g) acids react with _____ carbonates and -_____ hydrogen carbonates to produce _________ carbon dioxide _______ They don’t just taste “chalky”, they are chalk! 1 Ca. CO 3 (s) + 2 HCl (aq) 1 Ca. Cl 2 (aq) + 1 H 2 O (l) + 1 CO 2 (g) 1 Na. HCO 3 (s) + HC 2 H 3 O 2 (aq) 1 Na. C 2 H 3 O 2 (aq) + 1 H 2 O (l) + 1 CO 2 (g)

Acids & Bases I. Properties of Acids & Bases Write the balanced thermochemical equation for the reaction that occurs between: 1. Magnesium and Nitric acid 1 Mg (s) + 2 HNO 3 (aq) 2. Aluminum and Sulfuric acid 1 Mg(NO 3)2 (aq) + 1 H 2 (g) 2 Al (s) + 3 H 2 SO 4 (aq) 1 Al 2(SO 4)3 (aq) + 3 H 2 (g) 3. Calcium carbonate and Hydrobromic acid 1 Ca. CO 3 (s) + 2 HBr (aq) 1 Ca. Br 2 (aq) + 1 H 2 O (l) + 1 CO 2 (g) 4. Potassium Hydrogen carbonate and Hydrochloric acid 1 KHCO 3 (s) + 1 HCl (aq) 1 KCl (aq) + 1 H 2 O (l) + 1 CO 2 (g)

Acids & Bases I. Properties of Acids & Bases 1. Hypothesis: Which common household materials are acids or bases? 2. Prediction: 3. Gather Data: A. Safety: The acids and bases used in this lab are mildly corrosive and cause irritation of the skin, eyes, and mucous membranes. Avoid contact. Use caution. Goggles mandatory. B. Procedure: 1. Using a pipette, place 3 or 4 drops of each solution in a separate test well of a microplate.

Acids & Bases I. Properties of Acids & Bases 3. Gather Data: B. Procedure: 2. Test each liquid with litmus paper. Record results. 3. Test each liquid with 2 drops of phenolphthalein. Record results. Great Value™ Glass Cleaner Litmus Color (blue or pink) Phenolphthalein Color (clear or pink) Acid or Base Chlorox® Bleach Sprite® Hy-Vee® Vinegar Parson’s® All-Purpose Cleaner Hy-Vee® Orange Juice

Acids & Bases II. Ions in Solutions of Acids & Bases -the relative amounts of ____ H+ and ____ OH- ions in ____ aqueous _______ solution determine the relative ______, acidity _______ basicity or ____ neutrality of the _______, ____ solution Red tulip changes color in varying p. H aqueous _______ solution that -an _______ contains more ___ H+ than ____ OHis an ______ acidic _______ solution that -an aqueous _______ + OH- than H contains more ____ basic _______ solution is an _____ Purple iris changes color in varying p. H http: //bradley. edu/~campbell/demopix 5. html -an aqueous _______ solution that contains _____ equal amounts of ___ H+ and ____ OH- is _______ neutral

Acids & Bases II. Ions in Solutions of Acids & Bases -_______ aqueous ____ solutions that are neither ______ acids or _____ bases are _______, neutral but _____ water is neutral because it is ____ both _______ acid and a ____ base at the an ____ same time, containing _____ equal amounts of ___ H+ and ____ OHPurple carnation changes color in varying p. H polarity -because of its _______, water ______: self-ionizes _____ 1 H 2 O(l) Peony changes color in varying p. H http: //bradley. edu/~campbell/demopix 5. html 1 H+ (aq) + 1 OH-(aq) H+ forms a covalent -but the _______ bond with a ______ another _____ water ________, molecule producing the _____ hydronium ____ ion 2 H 2 O(l) 1 H 3 O+(aq) + 1 OH-(aq)

Acids & Bases III. The Arrhenius Model -according to ______ Svante _____, Arrhenius an of Acids and Bases ____ acid is a ____ substance that contains ____ hydrogen and _______ ionizes to produce hydrogen ____ ions in _______ aqueous _______ solution ____ -according to _____, ____ Arrhenius Hydrogen chloride is an _____ acid ____ 1 HCl (g) 1 H+ (aq) + 1 Cl- (aq) -according to _____, Arrhenius a _____ base is a substance hydroxide ____ that contains a _____ group and _____ dissociates to produce _____ hydroxide _____ ions in _______ aqueous ____ solution _____ -according to _____, Arrhenius ____ Sodium _____ hydroxide is a _____ base Svante August Arrhenius 1859 - 1927 1 Na. OH (s) 1 Na+ (aq) + 1 OH- (aq)

Acids & Bases IV. The Brønsted –Lowry Model -according to ____-______, Brønsted Lowry of Acids and Bases an _____ acid is a _____-____ hydrogen ion ______ donor and a _____ base is a ____hydrogen ____ ion ____ acceptor 1 HX (aq) + 1 H 2 O (l) Acid Base 1 H 3 O+(aq) + 1 X- (aq) Conjugate Acid Conjugate Base -the _____, acid ______, HX (aq) _____ dissolves in _____ water and _______ donates a ____ hydrogen ____ ion to a ______ water ____, molecule which acts as a _____ base hydrogen ____ ion by accepting ____ the ____ Johannes Nicolaus Brønsted 1879 - 1947 Thomas Martin Lowry 1874 - 1936 base that has ____ accepted a ___ H+ -a ____ donate a now has the ability to ______ H+ and so becomes an _____; acid ___, the _____ conjugate _____ acid

Acids & Bases IV. The Brønsted –Lowry Model -according to ____-______, Brønsted Lowry of Acids and Bases a ______ conjugate ____ acid is the species produced when a ____ base accepts a hydrogen ___ ion from an ____ acid ____ 1 HF (aq) + 1 H 2 O (l) Acid Base 1 H 3 O+(aq) + 1 F- (aq) Conjugate Acid Conjugate Base -a _____ conjugate ____ base is the ______ species that is left over from the ____ acid after it donates a ____ hydrogen ____ ion How is playing Hacky Sack Like Conjugate Acid-Base Pairs? Player who passed Footbag Player passing Footbag Playing Hacky Sack in Zurich, Switzerland http: //zurichdailyphoto. blogspot. com/2007/04/hacky-sack. html Player receiving Footbag Player who received Footbag Conjugate acid Acid Hydrogen ion Base Conjugate base

Acids & Bases IV. The Brønsted –Lowry Model of Acids and Bases Label the acid, base, conjugate acid, and conjugate base in the following: 1 NH 3 (aq) + 1 H 2 O (l) Base Acid 1 HBr (aq) + 1 H 2 O (l) Acid Base 1 CO 32 - (aq) + 1 H 2 O (l) Base Acid 1 HSO 4 - (aq) + 1 H 2 O (l) Acid Base 1 NH 4+(aq) + 1 OH- (aq) Conjugate Acid Conjugate Base Substances that can act as both an acid and a base are called amphoteric, as water is in these examples. 1 H 3 O+(aq) + 1 Br- (aq) Conjugate Acid Conjugate Base 1 HCO 3 -(aq) + 1 OH- (aq) Conjugate Acid Conjugate Base 1 H 3 O+(aq) + 1 SO 42 - (aq) Conjugate Acid Conjugate Base

Acids & Bases V. Monoprotic & Polyprotic Acids -____ HCl and ___ HF are _____ acids according to the _____ Arrhenius model _____ because they both contain hydrogen and they both donate _____ hydrogen ___ ion to an aqueous a ________ solution Chemical burns caused by Hydrofluoric acid http: //www. emedicine. com/emerg/topic 804. htm H H O C C H O H Even though acetic acid has 4 hydrogen atoms, only 1 of the 4 has a polar enough bond to be ionizable. The other 3 are practically nonpolar bonds. HCl and ___ HF are also -both __________ monoprotic _____ acids because each donates only ____ one hydrogen ___ ion per ____ molecule _____ -_____ HNO 3 (______ Nitric _____), acid ______ HCl. O 4 (_____ Perchloric _____), acid ____ HBr (______ Hydrobromic _____), acid and CH acetic or _____ 3 COOH (______ ethanoic _____) acid are other ____ monoprotic ______ acids _____

Acids & Bases V. Monoprotic & Polyprotic Acids -_____ acids that donate _____ more than ____ one _____ hydrogen ___ ion are called H _____ polyprotic C H H -______(_______ H 2 SO 4 Sulfuric _____) acid and C C ______(____ H 2 CO 3 Carbonic _____) acid are C C both _______ diprotic _____, acids while H C H H 3 PO 4 (_____ Phosphoric ____) acid and ______ H 3 BO 3 (______ Boric _____) acid are ______ H Benzene has 6 hydrogen atoms, triprotic ______ acids both _____ but none of the covalent bonds are polar enough to be ionizable, so benzene is not an acid at all. H O O O S O O H Sulfuric acid contains 2 highly polar ionizable covalent bonds P O H Phosphoric acid contains 3 highly polar ionizable covalent bonds

Acids & Bases V. Monoprotic & Polyprotic Acids -_____ polyprotic _____ acids donate more than ____ one ____ hydrogen ____ ion to H _______ aqueous _______ solution in more than O one ___ step O P O -the ____ triprotic ____ acid _____ Phosphoric H ____ acid donates __ 3 ____ hydrogen ____ ions O in __ 3 steps: H 1 H 3 PO 4 (aq) + 1 H 2 O (l) 1 H 3 O+(aq) + 1 H 2 PO 4 - (aq) + 1 H 2 O (l) 1 H 3 O+(aq) + 1 HPO 42 - (aq) + 1 H 2 O (l) 1 H 3 O+(aq) + 1 PO 43 - (aq)

Acids & Bases V. Monoprotic & Polyprotic Acids Write the steps for complete ionization of the following polyprotic acids: H 2 Se (aq) + H 2 O (l) H 3 O+(aq) + 1 HSe- (aq) + H 2 O (l) H 3 O+(aq) + Se 2 - (aq) H 3 As. O 4 (aq) + H 2 O (l) H 3 O+(aq) + H 2 As. O 4 - (aq) + H 2 O (l) H 3 O+(aq) + HAs. O 42 - (aq) + H 2 O (l) H 3 O+(aq) + As. O 43 - (aq) H 2 SO 3 (aq) + H 2 O (l) H 3 O+(aq) + HSO 31 - (aq) + H 2 O (l) H 3 O+(aq) + SO 32 - (aq)

Acids & Bases VI. Acid & Base Anhydrides -_____ anhydrides are _______ oxides that form _____ acids and _____ bases when added to ______ water 1 CO 2 (g) + 1 H 2 O (l) 1 H 2 CO 3 (aq) 2 NO 2 (g) + 1 H 2 O (l) 1 HNO 3 (aq) + 1 HNO 2 (aq) 1 SO 2 (g) + 1 H 2 O (l) 1 H 2 SO 3 (aq) 1 SO 3 (g) + 1 H 2 O (l) 1 H 2 SO 4 (aq) oxides of ______ nonmetallic elements -______ acids in _______ aqueous _______, solution produce _____ oxides of ____ metallic elements while ______ produce _____ bases in _______ aqueous ____ solution 1 Ca. O (s) + 1 H 2 O (l) 1 Ca 2+ (aq) + 2 OH- (aq) 1 Mg. O (s) + 1 H 2 O (l) 1 Mg 2+ (aq) + 2 OH- (aq)

Acids & Bases VII. Strength of Acids -______ strong _____ acids are _____ acids that ______ ionize _____ completely 1 HCl (aq) + 1 H 2 O (l) 1 H 3 O+ (aq) + 1 Cl- (aq) Hydrofluoric acid is considered a weak acid because it doesn’t ionize completely; it is expected to be a strong acid, because it is so corrosive, but its corrosiveness is due to the chemical reactivity of its anion, the fluoride ion. The strongest acids, the carborane superacids, are a million times stronger than concentrated sulfuric acid, but not at all corrosive because the anion to the acid is so unreactive. HC 2 H 3 O 2 (aq) -____ HCl (______ Hydrochloric _____), acid ______ HCl. O 4 (_____ Perchloric _____), acid _____ HNO 3 (______ Nitric ____), acid ____ HBr (______ Hydrobromic _____), acid ______ H 2 SO 4 (____ Sulfuric _____), acid and ___ HI (______ Hydroiodic acid are all ______ strong _____ acids _____) -______ weak _____ acids are _____ acids that ______ ionize only ____ partially + H 2 O (l) H 3 O+(aq) + C 2 H 3 O 2 - (aq) -____ HC 2 H 3 O 2 (______ Acetic _____), acid ______ H 2 CO 3 (____ Carbonic _____), acid ___ HF (______ Hydrofluoric ____), acid ______ H 3 BO 3 (_____ Boric _____), acid and _____ HCN Hydrocyanic ____) acid are _____ weak _____ acids (______

Acids & Bases VII. Strength of Acids -according to _______, Brønsted-Lowry the acid ____ on the _______ reactant side of the ____ forward _______ reaction produces a ____ conjugate ____ base on the ____ product forward _______ reaction by donating side of the _______ a hydrogen ___ ion ____ 1 HX (aq) + 1 H 2 O (l) Acid 1 H 3 O+(aq) + 1 X- (aq) Conjugate Base -if the ____ acid is a ______ strong ____, acid then its _____ conjugate ____ base is _____, weak that is, if the ____ acid readily _______ donates a ____ hydrogen ___, ion then its ____ conjugate ____ base is not very good at accepting hydrogen ___, ion or holding on to ____a ____ acid which is not very one, while a weak ____, good at _______ donating a ____ hydrogen ___ ion has a ________ strong conjugate base

Acids & Bases VII. Strength of Acids -the _____ ionization ____ equation for ______ Hydrocyanic _____ acid is: 1 HCN (aq) + 1 H 2 O (l) 1 H 3 O+(aq) + 1 CN- (aq) equilibrium ____ constant _____ expression for -the _____ ionization of ______ Hydrocyanic _____ acid is: the _____ Keq +]1[CN-]1 [H O 3 = [HCN]1[H 2 O]1 liquid _____ water is -the concentration ______ of ______ constant and so can be considered to be _______, _____ combined with ___ Keq to give the _____ acid _____ ionization _______, constant or ___ Ka Ka = [H 3 O+]1[CN-]1 [HCN]1

Acids & Bases VII. Strength of Acids Write ionization equations and acid ionization constant expressions for the following acids: HCl. O 2 (aq) + H 2 O (l) H 3 O+(aq) + Cl. O 2 - (aq) Ka = HNO 2 (aq) + H 2 O (l) HIO (aq) + H 2 O (l) H 3 O+(aq) + [H 3 O+]1[Cl. O 2 -]1 [HCl. O 2]1 + NO 2 - (aq) Ka = [H 3 O+]1[NO 2 -]1 [HNO 2]1 Ka = [H 3 O+]1[IO-]1 [HIO]1 IO- (aq)

Acids & Bases VIII. Strength of Bases-______ strong _____ bases are _____ bases that _____ dissociate _____ completely 1 Na. OH (s) 1 Na+ (aq) + 1 OH- (aq) -______ Na. OH (________), Sodium hydroxide _____ KOH (_________), Potassium hydroxide ______ Rb. OH (_____ Rubidium _____), _____ (________), hydroxide Cs. OH Cesium hydroxide _______ 2 Ca(OH)2(________), Calcium hydroxide and Ba(OH) Barium hydroxide are all ______ strong _____ bases (________) CH 3 NH 2 (aq) -______ weak _____ bases are _____ bases that dissociate ____ only ____ partially + H 2 O (l) CH 3 NH 3+(aq) + OH- (aq) -____ CH 3 NH 2 (______), methylamine ____ C 2 H 5 NH 2 (_____), ethylamine ____ NH 3 (____), ammonia and ____ C 6 H 5 NH 2 (______) aniline are all _____ weak ______ bases

Acids & Bases VIII. Strength of Bases -the ionization ________ equation for _____ hexylamine is: 1 C 6 H 13 NH 2 (aq) + 1 H 2 O (l) Base 1 OH-(aq) + 1 C 6 H 13 NH 3+ (aq) Conjugate Base Acid Conjugate Acid acid _____ ionization ____ constant -the ____ expression for the _____ ionization of ___________ hexylamine is: H H H H C C C H H H Hexylamine H N H Kb = [OH-]1 [C 6 H 13 NH 3+]1 [C 6 H 13 NH 2]1

Acids & Bases VIII. Strength of Bases Write ionization equations and base ionization constant expressions for the following bases: C 3 H 7 NH 2 (aq) + H 2 O (l) OH-(aq) + C 3 H 7 NH 3+ (aq) Kb = CO 32 -(aq) + H 2 O (l) [OH-]1 [C 3 H 7 NH 3+]1 [C 3 H 7 NH 2]1 OH-(aq) + HCO 3 - (aq) Kb = HSO 3 - (aq) + H 2 O (l) OH-(aq) + [OH-]1 [HCO 3 -]1 [CO 32 -]1 H 2 SO 3 (aq) Kb = [OH-]1 [H 2 SO 3]1 [HSO 3 -]1

Acids & Bases IX. Ion Product Constant for Water -the ionization ________ equation for ______ water is: H 2 O (l) + H 2 O (l) Base Acid OH-(aq) + H 3 O+ (aq) Conjugate Base Conjugate Acid equation can be -the ionization ________ simplified to: H 2 O (l) OH-(aq) + H+ (aq) equilibrium _______ constant -the _____ expression is: _____ Keq = [OH-]1 [H+]1 [H 2 O]1

Acids & Bases IX. Ion Product Constant for Water -since _____ water is a ______, liquid its _______ concentration is equal to its _______, density which is _______ constant at 1 + 1 Kw = [OH ] [H ] constant ______ temperature and a _______ pressure so the _____ equilibrium ____, Kw = (1 x 10 -7)1 constant _____ expression can be _______ -14 Kw = 1 x 10 simplified by _____ multiplying both sides by ______, [H 2 O] creating ion _______ product _______ constant ___ for the ___ water ___ Kw _____, K the ____self _____ ionization -at 298 _____, +] [H water produces ____ = of _____ [OH-] = _____ 1 x 10 -7 M and a ______ Kw = _________, 1 x 10 -7 M so ___ 1 x 10 -14

Acids & Bases IX. Ion Product Constant for Water What is the concentration of the hydroxide ion in an aqueous solution with a hydrogen ion concentration of 1 x 10 -5 M? Is the solution acidic, basic, or neutral? Kw = [H+][OH-] 1 x 10 -14 = (1 x 10 -5) [OH-] = 1 x 10 -9 M The solution is acidic, because the [H+] is greater (104) than the [OH-] What is the concentration of the hydrogen ion in an aqueous solution with a hydroxide ion concentration of 1 x 10 -3 M? Is the solution acidic, basic, or neutral? Kw = [H+][OH-] 1 x 10 -14 = [H+](1 x 10 -3) [H+] = 1 x 10 -11 M The solution is basic, because the [OH-] is greater (108) than the [H+]

Acids & Bases X. p. H (pondus hydrogenii) -in 1909, _____ Sørensen developed the ___ p. H (____ potential _____) hydrogen _____ scale as a way of conveniently expressing concentration of _____ acids and _____ bases the ______ p. H = -log [H+] What is the p. H of water? The number of +] p. H = -log [H decimal places in the p. H is equal to p. H = -log (1 x 10 -7) the number of significant digits 1 sig. fig. in [H ], p. H = 7. 0 1 decimal in the [H ] place in p. H What is the p. H of an aqueous solution in which the [H+] = 1. 0 x 10 -2 M? + + Sørensen 1868 - 1939 p. H = -log [H+] p. H = -log (1. 0 x 10 -2) 2 sig. figs. in [H ], p. H = 2. 00 2 decimal place in p. H +

Acids & Bases X. p. H (pondus hydrogenii) 1. Hypothesis: What is the relationship between the concentration of an acid and its p. H? 2. Prediction: 3. Gather Data: A. Safety: The acids used in this lab are corrosive and cause irritation and damage to the skin, eyes, and mucous membranes. Avoid contact. Use caution. Goggles mandatory. B. Procedure: Serial Dilution 1. Using a pipette, place 10 drops of 1. 0 M HCl in test well 1 A of a microplate.

Acids & Bases X. p. H (pondus hydrogenii) 3. Gather Data: B. Procedure: 2. Rinse the pipette, and transfer 1 drop of acid solution from test well 1 A to test well 2 A, and add 9 drops of distilled water. 3. Repeat Step 2, transferring 1 drop of acid solution from test well 2 A to test well 3 A and adding 9 drops of distilled water. 4. Repeat Step 2 six more times, each time transferring 1 drop of acid solution from the previous test well and adding 9 drops of distilled water.

Acids & Bases X. p. H (pondus hydrogenii) 3. Gather Data: B. Procedure: 5. Test the p. H in each well with p. H indicator paper. Record. 6. Test the p. H in each well with 1 drop of universal indicator solution. Record. Test Well Number [H+] Concentration p. H paper p. H Universal Indicator A 1 A 2 A 3 A 4 A 5 A 6 B 1 B 2

Acids & Bases X. p. H (pondus hydrogenii) 4. Analyze Data: A. What is [H+] in test well A 4? ________. B. What is [H+] in test well A 6? ________. C. What is theoretical p. H in test well A 2? ________. D. What is theoretical p. H in test well B 2? ________. E. The color of p. H paper in test well A 1 was _______, indicating an approximate p. H of _______. F. In test well A 2 universal indicator was ____ in color. 5. Draw Conclusions: A. Each step in the serial dilution ______ the concentration of the hydrogen ion by a factor of _______ and _____ the p. H by a factor of _______

Acids & Bases XI. p. OH (potential Hydroxide) -the _______, basicity or ____, alkalinity of a _______ solution can be expressed by the ____, or ____ p. OH potential _____: Hydroxide p. OH = -log [OH-] What is the p. OH of water? What is the p. H of an aqueous solution -] = 1. 0 x 10 -3 M? in which the [OH p. OH = -log [OH ] -] -7 p. OH = -log [OH p. OH = -log (1 x 10 ) -3) p. OH = -log (1. 0 x 10 p. OH = 7. 0 p. OH = 3. 00 What is the p. OH of an aqueous solution in which the [OH-] = 1. 00 x 10 -6 M? Kw = [OH-][H+] p. OH = -log [OH-] 1 x 10 -14 = (1 x 10 -7) p. OH = -log (1. 00 x 10 -6) 14 = p. H + p. OH = 6. 000 p. H = 11. 00

Acids & Bases XI. p. OH (potential Hydroxide) What is the p. H and the p. OH of an aqueous solution with a hydroxide ion concentration of 1. 0 x 10 -6 M? Is the solution acidic, basic, or neutral? p. OH = -log [OH-] p. OH = 6. 00 p. OH = -log (1. 0 x 10 -6) 14 = p. H + p. OH p. H = 8. 00 basic What is the p. H and the p. OH of an aqueous solution with a hydroxide ion concentration of 6. 5 x 10 -4 M? Is the solution acidic, basic, or neutral? p. OH = -log (6. 5 x 10 -4) p. H = 10. 81 p. OH = 3. 19 basic What is the p. H and the p. OH of an aqueous solution with a hydrogen ion concentration of 3. 6 x 10 -9 M? Is the solution acidic, basic, or neutral? p. H = -log (3. 6 x 10 -9) p. OH = 5. 56 p. H = 8. 44 basic

Acids & Bases XI. p. OH (potential Hydroxide) What is the hydrogen ion concentration and the hydroxide ion concentration of a person’s blood that has a p. H of 7. 40 at 298 K? p. H = -log [H+] 7. 40 = -log [H+] = 4. 0 x 10 -8 M 6. 60 = -log [OH-] 14 = 7. 40 + p. OH [OH-] = 2. 5 x 10 -7 M What is the hydrogen ion concentration and the hydroxide ion concentration of an aqueous solution that has a p. H of 2. 37 at 298 K? Multiply [H ][OH ] 2. 37 = -log [H+] 11. 63 = -log [OH-] to check your answer [H+] = 4. 3 x 10 -3 M [OH-] = 2. 3 x 10 -12 M Kw = (4. 3 x 10 -3)(2. 3 x 10 -12) What is the hydrogen ion concentration and the hydroxide ion concentration of an aqueous solution that has a p. H of 11. 05 at 298 K? + [H+] [OH-] - Multiply [H+][OH-] to check your answer 11. 05 = -log 2. 95 = -log [H+] = 8. 9 x 10 -12 M [OH-] = 1. 1 x 10 -3 M Kw = (8. 9 x 10 -12)(1. 1 x 10 -3)

Acids & Bases XII. Calculating p. H of Strong Acids and Strong Bases What is the p. H of a 1. 0 M HI solution? p. H = -log [H+] 1 HI (aq) p. H = -log (1. 0) p. H = 0. 00 1. 0 M 1 H+ (aq) + 1 I- (aq) 1. 0 M What is the p. H of a 0. 050 M HNO 3 solution? 1 HNO 3 (aq) 1 H+ (aq) + 0. 050 M 1 NO 3 - (aq) 0. 050 M p. H = -log [H+] p. H = -log (0. 050) p. H = 1. 30 What is the p. OH of a 2. 4 x 10 -5 M Mg(OH)2 solution? 1 Mg(OH)2 (s) 1 Mg 2+ (aq) + 2 OH- (aq) p. OH = 2. 4 x 10 M 4. 8 x 10 M p. OH = p. H = -5 -5 -5 -log [OH-] -log (4. 8 x 10 -5) 4. 32 9. 68

Acids & Bases XIII. Calculating p. H of Weak Acids and Weak Bases What is Ka of a 0. 100 M formic (methanoic) acid solution with p. H 2. 38? 1 HCOOH (aq) 0. 100 M 1 HCOO-(aq) + 1 H+ (aq) 4. 2 x 10 -3 M p. H = -log [H+] 2. 38 = -log [H+] [HCOO-] [HCOOH] Ka = [HCOO-][H+] [HCOOH] 4. 2 x 10 -3 M = = = 4. 2 x 10 -3 M 0. 100 M - 0. 0042 M 0. 096 M Ka = (4. 2 x 10 -3 ) (0. 096 ) Ka = 1. 8 x 10 -4

Acids & Bases XIII. Calculating p. H of Weak Acids and Weak Bases What is Ka of a 0. 220 M arsenic acid solution with p. H 1. 50? 1 H 3 As. O 4 (aq) 0. 220 M 3. 2 x 10 -2 M p. H = -log [H+] 1. 50 = -log [H+] Ka = 1 H 2 As. O 4 -(aq) + 1 H+ (aq) 3. 2 x 10 -2 M [H+] [H 2 As. O 4 -] [H 3 As. O 4] [H 2 As. O 4 -][H+] [H 3 As. O 4] = = = Ka = 3. 2 x 10 -2 M 0. 220 M - 0. 032 M 0. 188 M (3. 2 x 10 -2 ) (0. 188 ) Ka = 5. 4 x 10 -3

Acids & Bases XIII. Calculating p. H of Weak Acids and Weak Bases What is Ka of a 0. 0400 M chlorous acid solution with p. H 1. 80? 1 HCl. O 2 (aq) 1 Cl. O 2 -(aq) + 1 H+ (aq) 0. 0400 M 1. 6 x 10 -2 M p. H = -log [H+] 1. 80 = -log [H+] Ka = [Cl. O 2 -][H+] [HCl. O 2] 1. 6 x 10 -2 M [H+] [Cl. O 2 -] [HCl. O 2] = = = Ka = 1. 6 x 10 -2 M 0. 0400 M - 0. 016 M 0. 024 M (1. 6 x 10 -2 ) (0. 024 ) Ka = 1. 1 x 10 -2

Acids & Bases XIII. Calculating p. H of Weak Acids and Weak Bases What is Ka of a 1. 000 M propanoic acid solution with p. H 2. 43? 1 HC 3 H 5 O 2 (aq) 1. 000 M 3. 7 x 10 -3 M p. H = -log [H+] 2. 43 = -log [H+] Ka = 1 C 3 H 5 O 2 -(aq) + 1 H+ (aq) 3. 7 x 10 -3 M [H+] [C 3 H 5 O 2 -] [HC 3 H 5 O 2] [C 3 H 5 O 2 -][H+] [HC 3 H 5 O 2] = = = Ka = 3. 7 x 10 -3 M 1. 000 M - 0. 0037 M 0. 9963 M (3. 7 x 10 -3 ) (0. 9963 ) Ka = 1. 4 x 10 -5

Acids & Bases XIV. Neutralization -when an ____ acid and a base _____, react the resulting _______ solution has _____ properties that are characteristic of _______ neither an ____ acid or a base neutralization _______ reaction is a ______double -a ______ replacement _______ reaction in which an ____ acid and a ______ base react in _______ aqueous ____ solution to produce a ____ salt and _____ water 1 Mg(OH)2 (aq) + 2 HCl (aq) Milk of Magnesia is a Magnesium hydroxide suspension used to neutralize stomach acid base acid 1 Mg. Cl 2 (aq) + 2 H 2 O (l) salt water -a ____ salt is an _____ ionic _____ compound made up of the cation from the ____ base and the _____ anion from the ______ acid ____ net _____ ionic ____ equation for a ______ neutralization -the ___ reaction is: _______ OH- (aq) + H+ (aq) H 2 O (l)

Acids & Bases XIV. Neutralization Write the complete balanced thermochemical equations for the following neutralization reactions and name the products: Nitric acid + Cesium hydroxide 1 HNO 3 (aq) + acid 1 Cs. OH (aq) base 1 Cs. NO 3 (aq)+ 1 H 2 O (l) Cesium nitrate water Hydrobromic acid + Calcium hydroxide 2 HBr (aq) + 1 Ca(OH)2 (aq) acid base 1 Ca. Br 2 (aq) + 2 H 2 O (l) Calcium bromide water Sulfuric acid + Potassium hydroxide 1 H 2 SO 4 (aq) + 2 KOH (aq) acid base 1 K 2 SO 4 (aq) + 2 H 2 O (l) Potassium sulfate water

Acids & Bases XV. Titration -a _______is titration a method for determining an ____ unknown ______ concentration of a solution by _______ reacting a ______ known ______ of a different _______ solution of ______ volume known concentration ______ -to find the ____ unknown ______ concentration of a ______ known ______ of ____ volume base solution, you can ______ titrate the known volume acid solution with a ______ of an ____ known ______ concentration of ______ electronic p. H meter 1 HCl (aq) + acid 1 m. L HCl sol. x base 1 L HCl sol. _______ 1000 m. L HCl sol. M = 1 Na. OH (aq) x salt 1 mole HCl ______ 1 L HCl sol. 0. 001 mole Na. OH ________ 10 m. L Na. OH sol. 1 Na. Cl (aq) + 1 H 2 O (l) x x water 1 mole Na. OH ________ = 1 mole HCl 1000 m. L Na. OH sol. ________ 1 L Na. OH sol. = 0. 001 mole Na. OH 0. 1 M Na. OH

Acids & Bases XV. Titration What is the molarity of a Cs. OH solution if 30. 0 m. L of the solution is neutralized by 26. 4 m. L of 0. 250 M HBr solution? 1 HBr (aq) 26. 4 m. L HBr sol. x + 1 Cs. OH (aq) 1 L HBr sol. _______ 1000 m. L HBr sol. M = x 1 Cs. Br (aq) + 1 H 2 O (l) 0. 250 mole HBr x ______ 1 L HBr sol. 0. 00660 mole Cs. OH x ________ 30. 0 m. L Cs. OH sol. 1 mole Cs. OH ________ = 0. 00660 mole Cs. OH 1 mole HBr 1000 m. L Cs. OH sol. ________ 1 L Cs. OH sol. = 0. 220 M Cs. OH What is the molarity of a nitric acid solution if 20. 00 m. L of the solution is neutralized by 43. 33 m. L of 0. 1000 M KOH solution? 1 HNO 3 (aq) + 1 L KOH sol. x 43. 33 m. L KOH sol. x _______ 1000 m. L KOH sol. 1 KOH (aq) 1 KNO 3 (aq) + 1 H 2 O (l) 0. 1000 mole KOH x ________ 1 mole HNO 3 _______ = 4. 333 x 10 -3 mole HNO 3 1 L KOH sol. 1 mole KOH x 10 -3 mole HNO 3 M = 4. 333 ________ 20. 00 m. L HNO 3 sol. x 1000 m. L HNO 3 sol. ________ 1 L HNO 3 sol. = 0. 2167 M HNO 3

Acids & Bases XV. Titration -during the course of a _______, titration a known _______ volume of a ___________ is added until solution of known concentration the _____ equivalence _____ point is reached, at which the number of ______ moles of ____ H+ equals the _______ number of _______ moles of _____ OH______ -corresponding closely with the _____ equivalence _____ point is the ___ end _____, point at which the ____ indicator changes _____ color Adding indicator Titrating End Point

Acids & Bases XVI. Buffered Solutions -_______ buffers are _____ solutions that _____ resist changes in ___ p. H buffer is a _______ mixture of a _____ weak ____ acid -a ______ conjugate ____ base and its _____ Weak acid HF (aq) Human blood is buffered by the weak acid carbonic acid (H 2 CO 3) and its conjugate base, hydrogen carbonate (HCO 3 -) Conjugate base H+ (aq) + F- (aq) H+ HF (aq) Adding an acid, raising [H+] H+ (aq) + F- (aq) Equilibrium shifts to the left, lowering [H+] H 2 O (l) H+ (aq) + OH- (aq) OH- Adding a base, raising [OH-] H 2 O (l) H+ (aq) + OH- (aq) Equilibrium shifts to the left, lowering [OH-]

Acids & Bases XVI. Buffered Solutions -a ______ buffer can also be a _______ mixture of a _____ weak ____ base and its _____ conjugate ____ acid Weak base Conjugate acid NH 3 (aq) + H 2 O (l) NH 4+ (aq) + OH- (aq) OH- Adding a base, raising [OH-] NH 3 (aq) + H 2 O (l) NH 4+ (aq) + OH- (aq) Equilibrium shifts to the left, lowering [OH-] H 2 O (l) H+ (aq) + OH- (aq) H+ H 2 O (l) Adding an acid, raising [H+] H+ (aq) + OH- (aq) Equilibrium shifts to the left, lowering [H+]

Acids & Bases XVI. Buffered Solutions What is the p. H of buffer system made by mixing equal amounts of H 2 PO 4 - and HPO 42 -? H 2 PO 4 - (aq) H+(aq) Ka = 6. 2 x 10 -8 = + HPO 42 - (aq) [H+] [HPO 42 -] [H 2 PO 4 -] 6. 2 x 10 -8 = [H+] p. H = -log (6. 2 x 10 -8) p. H = 7. 21