1 "#$%&''()*+,) "./012(') %')925#%) 1. List five properties of acids that are in your textbook. Acids conduct electricity, taste sour, neutralize bases, change the color of indicators, and react with some metals to produce hydrogen. 2. List five properties of bases that are in your textbook. Bases conduct electricity, taste bitter, neutralize acids, change the color of indicators, and feel slippery. 3. Make some brief notes on the commercial acids: HCl and H 2 SO 4 (p 112). HCl five common use H 2 SO 4 five common use 4. Make some brief notes on the commercial base NaOH five common uses. 5. Describe the difference between a concentrated and dilute acid (hint: concentration refers to the molarity). Describe their relative conductivities. Concentrated means relatively high molarity and dilute means relatively low molarity. 6. Describe the difference between a strong and weak acid (p ). Use two examples and write equations to support your answer. Describe their relative conductivities. A strong acid completely ionizes and a weak acid partially ionizes. 7. Describe a situation where a strong acid would have the same conductivity as a weak acid (hint: think about concentration). A weak acid could have a high molarity and the strong acid could have a low molarity. Complete this worksheet for next period. Read pages for homework. Complete each acid reaction. Label each reactant or product as an acid or base. The first on is done for you. 1. HCN + H 2 O H 3 O + + CN Acid Base Acid Base 2. H 3 C 6 O 7 + H 2 O H 2 C 6 O 7 + H 3 O + acid base base acid 3. H 3 PO 4 + H 2 O H 2 PO 4 + H 3 O + acid base base acid
2 4. HF + H 2 O F + H 3 O + acid base base acid 5. H 2 CO 3 + H 2 O HCO 3 + H 3 O + acid base base acid 6. + NH 4 + H 2 O NH 3 + H 3 O + acid base base acid 7. CH 3 COOH + H 2 O CH 3 COO + H 3 O + acid base base acid 8. HCl + H 2 O Cl + H 3 O + acid base base acid 9. HNO 3 + H 2 O H 3 O + + NO 3 acid base acid base Write the equilibrium expression (Ka) for the first seven above reactions. 10. Ka = [H 3 O + ] [ CN ] 14. Ka = [H 3 O + ] [HCO 3 ] [HCN] [H 2 CO 3 ] 11. Ka = [H 3 O + ] [H 2 C 6 O 7 ] 15. Ka = [H 3 O + ] [NH 3 ] [H 3 C 6 O 7 ] [NH + 4 ] 12. Ka = [H 3 O + ] [H 2 PO 4 ] 16. Ka = [H 3 O + ] [CH 3 COO ] [H 3 PO 4 ] [CH 3 COOH] 13. Ka = [H 3 O + ] [F ] [HF] 17. Which acids are strong? The six on the top of the acid chart are strong. 18. What does the term strong acid mean? They complete ionization into ions. Such as: HCl + H 2 O Cl + H 3 O Why is it impossible to write an equilibrium expression for a strong acid? Ka = [H 3 O + ] [Cl ] [HCl] [HCl] is equal to zero and in math numbers divided by zero are undefined. 20. Which acids are weak? All acids listed on the acid chart below the top six. 23. What does the term weak acid mean? Incomplete ionization. Such as: HF + H 2 O F + H 3 O Explain the difference between a strong and weak acid in terms of electrical conductivity. A strong acid is a good conductor. A weak acid conducts but not so good.
3 Acid Conjugate Base Base Conjugate Acid 14. HNO 2 NO HSO 3 SO H 2 O 2 HO HCOO HCOOH 17. IO 3 HIO NH 3 + NH HS S CH 3 COO CH 3 COOH 22. H 2 O OH 23. H 2 O H 3 O + Define: 22. Bronsted acid a proton donor 23. Bronsted base a proton acceptor 24. Arrhenius acid a substance that ionizes in water to produce H Arrhenius base a substance that ionizes in water to produce OH 26. List the six strong acids. HCLO 4 HI HBr HCl HNO 3 H 2 SO Rank the acids in order of decreasing strength. HCl HSO 4 H 3 PO 4 HF H 2 CO 3 H 2 S 28. What would you rather drink vinegar or hydrochloric acid? Explain. Vinegar. It is a weak acid and produces much less H ion which is the corrosive part of an acid.
4 "#$%&''()*+,) "./012(') %')925#%) Complete each reaction. Label each reactant or product as an acid or base. 1. HCN + H 2 O H 3 O + + CN 2. HCl + H 2 O H 3 O + + Cl 3. HF + H 2 O H 3 O + + F 4. F + H 2 O HF + OH 5. HSO 4 (acid) + 6. NH 4 + H 2 O H 3 O + + SO H 2 O H 3 O + + NH HPO 4 (base) + H 2 O H 2 PO 4 + OH Acid Conjugate Base Base Conjugate Acid 8. HCO 3 2 CO 3 9. CH 3 COO CH 3 COOH HPO 4 3 PO IO 3 HIO H 2 O OH 13. NH 2 NH HS S C 2 H 5 SO 7 2 HC 2 H 5 SO Circle the strong bases. Fe(OH) 3 NaOH CsOH KOH Zn(OH) 2 Sr(OH) 2 Ba(OH) 2 Ca(OH) Rank the following acids from strongest to weakest. H 2 S CH 3 COOH H 2 PO 4 HI HCl HF Rank the following bases from the strongest to weakest. H 2 O F NH 3 2 SO 3 HSO 3 NaOH
5 19. i) Write the reaction of H 3 BO 3 with water (remove one H + only because it is a weak acid). H 3 BO 3 + H 2 O H 2 BO 3 + H 3 O + ii) Write the K a expression for the above. [H 3 O + ][H 2 BO 3 ] K a = [H 3 BO 3 ] iii) What is the ionization constant for the acid (use your table). K a = 7.3 x List six strong acids. HClO 4 HI HBr HCl HNO 3 H 2 SO List six strong bases. NaOH KOH LiOH RbOH CsOH Ba(OH) List six weak acids in order of decreasing strength (use your acid/base table). HIO 3 H 2 C 2 O 4 H 2 SO 3 HSO 4 H 3 PO 4 HNO List six weak bases in order of decreasing strength (use your acid/base table). PO 4 3 CO 3 2 CN NH 3 H 2 BO 3 HS
6 "#$%&''()*+,) %./0)12.3)4(#'/0(&)5678'%) Acidbase reactions can be considered to be a competition for protons. A stronger acid can cause a weaker acid to act like a base. Label the acids and bases. Complete the reaction. State if the reactants or products are favoured. 1. HSO 4 + HPO 4 2 SO H 2 PO 4 Acid Base Base Acid Products are favoured as HSO 4 is a stronger acid than H 2 PO 4 2. HCN + H 2 O H 3 O + + CN Acid Base Acid Base Reactants are favoured as H 3 O + 3. HCO 3 is a stronger acid than HCN. + H 2 S H 2 CO 3 + HS Base Acid Acid Base Reactants are favoured as H 2 CO 3 is a stronger acid than H 2 S 4. HPO NH 4 + H 2 PO 4 Base Acid Acid Base Reactants are favoured as H 2 PO 4 is a stronger acid than NH NH 3 + H 2 O NH NH 3 + OH Base Acid Acid Base Reactants are favoured as OH is a stronger base than NH H 2 PO 4 + NH 3 2 HPO NH 4 Acid Base Base Acid 2 Products are favoured as NH 3 is a stronger base than HPO 4 7. HCO 3 + HF H 2 CO 3 + F Base Acid Acid Base Products are favoured as HF is a stronger acid than H 2 CO 3 8. Complete each equation and indicate if reactants or products are favoured. Label each acid or base. HSO HCO 3 H 2 CO 3 + SO 4 products are favoured H 2 PO 4 + HC0 3 HPO H 2 CO 3 reactants are favoured HS0 3 + HPO 4 2 H 2 PO 4 + SO 3 2 products are favoured NH 3 + HC 2 O 4 NH C 2 O 4 2 products are favoured 9. Explain why HF (aq) is a better conductor than HCN (aq). HF is a stronger acid and creates more ions. 10. Which is a stronger acid in water, HCl or HI? Explain Both are strong acids and have the same strength as both completely ionize to from H +.
7 11. State the important ion produced by an acid and a base. Acid: H + or H 3 O + Base: OH 12. Which is the stronger base? Which produces the least OH? F is the weaker base and produces the least OH CO 2 3 is the stronger base 13. Define a Bronsted/Lowry acid and base. An acid is a proton donor and a base is a proton acceptor. 14. Define an Arrhenius acid and base. An acid ionizes in water to produce H + and a base ionizes in water to produce OH. 17. Define conjugate pairs. Acid base pairs that differ by one proton. 18. Give conjugate acids for: HS, NH 3, HPO 2 4, OH, H 2 O, NH 3, 2 CO 3 H 2 S + NH 4 H 2 PO 4 HOH H 3 O + + NH 4 HCO Give conjugate bases for: +, NH 4 HF, H 2 PO 4, H 3 O +, OH, HCO 3, H 2 O NH 3 F 2 HPO 4 HOH O 2 2 CO 3 OH
8 1. What is the strongest acid that can exist in water? Write an equation to show how a stronger acid would be reduced in strength by the leveling effect of water. H 3 O + HCl + H 2 O H 3 O + + Cl 2. What is the strongest base that can exist in water? Write an equation to show how a stronger base would be reduced in strength by the leveling effect of water. OH NaOH Na + + OH 3. List three strong acids and three strong bases. HCl HI HClO 4 NaOH KOH LiOH 4. Rank the acids in decreasing strength: HClO 4 1 K a is very large HClO 3 2 K a =1.2x10 2 HClO 2 3 K a =8.0x10 5 HClO 4 K a =4.4x For an oxy acid what is the relationship between the number of O s and acid strength? (Compare H 2 S0 4 and H 2 S0 3 ) The more O s the stronger the acid. 6.Which acid is stronger? HI0 3 or HIO 2 7.Which produces more H 3 0 +? H 2 CO 3 or HS0 4 8.Which produces more OH? F or HC0 3 9.Which conducts better NH 3 or NaOH (both.1m)? Why? NaOH is a strong base. 10.Which conducts better HF or HCN (both.1m)? Why? HF is a stronger acid. 11. Compare and contrast a strong and weak acid in terms of degree of ionization, size of k a, conductivity, and concentration of H +. Strong acid: complete ionization, very large Ka, good conductor, high [H + ]. Weak acid: partial ionization, small Ka, OK conductor, low [H + ].
9 Classify each formula as an acid anhydride, basic anhydride, strong acid, weak acid, strong, or weak base. For each formula write an equation to show how it reacts with water. For anhydrides write two equations. Formula Classification Reaction 12. Na 2 O basic anhydride Na 2 O + H 2 O 2NaOH 13. CaO basic anhydride CaO + H 2 O Ca(OH) SO 3 acid anhydride SO 3 + H 2 O H 2 SO CO 2 acid anhydride CO 2 + H 2 O H 2 CO SO 2 acid anhydride SO 2 + H 2 O H 2 SO HCl strong acid HCl + H 2 O H 3 O + + Cl 18. NH 3 weak base NH 3 + H 2 O NH OH 19. NaOH strong base NaOH Na + + OH 20. HF weak acid HF + H 2 O H 3 O + + F 21. H 3 PO 4 weak acid H 3 PO 4 + H 2 O H 3 O + + H 2 PO 4
10 "#$%&''()*+,)./#"0.%1%)"2)340(%)45/)6'47(1"5%)"2)871/%)45/)94%'%) Describe each as an acid, base, neutral salt, acidic salt, or basic salt. For each salt write a parent acidbase formation equation, dissociation equation, and hydrolysis equation (only for acidic and basic salts). For acids and bases write an equation to show how each reacts with water. 1. NH 3 weak base NH 3 + H 2 O NH OH 2. KCl neutral salt HCl + KOH KCl + H 2 O KCl K + + Cl 3. HNO 3 strong acid HNO 3 + H 2 O H 3 O + + NO 3 4. NaHCO 3 basic salt H 2 CO 3 + NaOH NaHCO 3 + H 2 O NaHCO Na + + HCO 3 HCO 3 + H 2 O H 2 CO 3 + OH 5. RbOH strong base RbOH Rb + + OH 6. AlCl 3 acid salt 3HCl + Al(OH) 3 AlCl 3 + 3H 2 O AlCl 3 Al Cl Al(H 2 O) 6 3+ Al(H 2 O) 5 (OH) 2+ + H +
11 "#$%&''()*+,)./#"0.%1%)"2)340(%)45/)6'47(1"5%)"2)871/%)45/)94%'%) 7. H 2 C 2 O 4 weak acid H 2 C 2 O 4 + H 2 O H 3 O + + HC 2 O 4 8. NaC 6 H 5 O basic salt C 6 H 5 OH + NaOH NaC 6 H 5 O + H 2 O NaC 6 H 5 O Na + + C 6 H 5 O C 6 H 5 O + H 2 O C 6 H 5 OH + OH 9. Co(NO 3 ) 3 acid salt 3HNO 3 + Co(OH) 3 Co(NO 3 ) 3 + 3H 2 O Co(NO 3 ) 3 Co NO 3 Co(H 2 O) 6 3+ Co(H 2 O) 5 (OH) 2+ + H Na 2 CO 3 basic salt H 2 CO 3 + 2NaOH Na 2 CO 3 + 2H 2 O Na 2 CO 3 2Na + + CO 3 2 CO H 2 O HCO 3 + OH
12 "#$%&''()*+,)./#"0.%1%)"2)340(%)45/)6'47(1"5%)"2)871/%)45/)94%'%) Describe each as an acid, base, neutral salt, acidic salt, or basic salt. For each salt write a parent acidbase formation equation, dissociation equation, and hydrolysis equation (only for acidic and basic salts). For acids and bases write an equation to show how each reacts with water. 1. NH 3 weak base NH 3 + H 2 O NH OH 2. NaCl neutral salt NaCl Na + + Cl 3. HCl strong acid HCl + H 2 O H 3 O + + Cl 4. NaCN basic salt NaCN Na + + CN CN + H 2 O HCN + OH 5. NaOH strong base NaOH Na + + OH 6. FeCl 3 acid salt FeCl 3 Fe Cl Fe(H 2 O) 6 3+ Fe(H 2 O) 5 (OH) 2+ + H + 7. HF weak acid HF + H 2 O H 3 O + + F 8. LiHCO 3 basic salt LiHCO 3 Li + + HCO 3 HCO 3 + H 2 O H 2 CO 3 + OH
13 "#$%&''()*+,)./#"0.%1%)"2)340(%)45/)6'47(1"5%)"2)871/%)45/)94%'%) 9. Fe(NO 3 ) 3 acid salt Fe(NO 3 ) 3 Fe NO 3 Fe(H 2 O) 6 3+ Fe(H 2 O) 5 (OH) 2+ + H MgCO 3 basic salt MgCO 3 Mg CO 3 2 CO 3 + H 2 O HCO 3 + OH 11. H 2 S weak acid H 2 S + H 2 O H 3 O + + HS 12. HF weak acid HF + H 2 O H 3 O + + F 13. CaI 2 neutral salt CaI 2 Ca I 14. Mg(OH) 2 weak base Mg(OH) 2 Mg OH 15. Ba(OH) 2 strong base Ba(OH) 2 Ba OH 16. Describe why Tums (CaCO 3 ) neutralizes stomach acid. It is a weak base and will neutralize acid. basic salt CaCO 3 Ca +2 + CO 3 2 CO H 2 O HCO 3 + OH 17. Describe why Mg(OH) 2 is used in Milk of Magnesia as an antacid instead of NaOH. Mg(OH) 2 is weak base and releases OH slowly, whereas NaOH is a strong base which releases OH in high concentrations which is corrosive. Mg(OH) 2 Mg OH NaOH Na + + OH
14 "#$%&''()*+,).)/01)2.)3/4564/(7"0%) Complete the chart: [H + ] [OH ] ph poh Acid/base/neutral x 10 3 M 1.43 x M acid x M 8.75 x 10 2 M base x 10 8 M 2.1 x 10 7 M base x M 1.0 x 10 4 M base x 10 7 M 1.0 x 10 7 M Neutral (2sig figs) 6. 5 x 10 4 M 2 x M acid x 10 3 M 3.57 x M acid x M 2.0 x 10 5 M base x 10 5 M 4.7 x M acid 10. Calculate the [H + ], [OH ], ph and poh for a 0.20 M Ba(OH) 2 solution. Ba(OH) 2 Ba OH 0.20M 0.20M 0.40M [OH ] = 0.40 M [H + ] = 2.5 x M ph = poh = Calculate the [H + ], [OH ], ph and poh for a M HCl solution. HCl H + + Cl 0.030M 0.030M [H + ] = 0.030M [OH ] = 3.3 x M ph = 1.52 poh = Calculate the [H + ], [OH ], ph and poh for a 0.20 M NaOH solution. NaOH Na + + OH 0.20M 0.20M 0.20M [OH ] = 0.20 M [H + ] = 5.0 x M ph = poh = ml of 0.20 M HCl is added to ml of water, calculate the ph of the solution. HCl H + + Cl x 0.20 M = M M ph = Log[H + ] =
15 ml of M HCl is diluted to a final volume of ml with water, calculate the ph. HCl H + + Cl x M = M M ph = Log[H + ] = ) ml of 0.40 M Ba(OH) 2 is placed in a ml volumetric flask and filled to the mark with water, calculate the ph of the solution. Ba(OH) 2 Ba OH x 0.40 M = 0.12 M 0.12 M 0.24 M poh = Log[OH ] = 0.62 ph = poh = ml of 0.20 M Sr(OH) 2 is diluted by adding ml of water, calculate the ph of the solution. Sr(OH) 2 Sr OH x 0.20 M = M M M poh = Log[OH ] = 0.78 ph = poh = Calculate the ph of a saturated solution of 0.40M Ba(OH) 2 when 25 ml was added 25.0 ml of water. Ba(OH) 2 Ba OH (25)0.40 M 0.20 M 0.40 M (50) [OH ] = 0.40 poh = 0.40 ph = 13.60
16 "#$%&''()*+,).)/012310(4"5%)6"#)'0$)7248%) 1. Calculate the [H + ], [OH ], ph, and poh for 0.20 M HCN. HCN H + + CN I 0.20 M 0 0 C x x x E 0.20 x x x x 2 = 4.9 x x x = 9.9 x 10 6 M [H + ] = 9.9 x 10 6 M [OH ] = 1.0 x 10 9 M ph = 5.00 poh = Calculate the [H + ], [OH ], ph, and poh for 2.20 M HF. [H + ] = 2.8 x 10 2 M [OH ] = 3.6 x M ph = 1.56 poh = Calculate the [H + ], [OH ], ph, and poh for M CH 3 COOH. [H + ] = 3.8 x 10 3 M [OH ] = 2.6 x M ph = 2.42 poh = Calculate the [H + ], [OH ], ph, and poh for 1.65 M H 3 BO 3. [H + ] = 3.5 x 10 5 M [OH ] = 2.9 x M ph = 4.46 poh = Calculate the ph of a saturated solution of Mg(OH) 2. Mg(OH) 2 Mg OH x x 2x Ksp = [Mg 2+ ][OH ] x = 4x 3 [OH ] = 2x = 2.22 x 10 4 M ph = 10.3
17 6. Calculate the ph of a M weak diprotic acid with a Ka = 1.8 x H 2 X H + + X Note only lose one proton for any weak acid I M 0 0 C x x x E 0.20 x x x Small Ka approximation x = 0 x 2 = 1.8 x x = 6.0 x 10 4 M [H + ] = 6.0 x 10 4 M [OH ] = 1.7 x M ph = 3.22 poh = ml of 0.20M Sr(OH) 2 is diluted by adding ml of water, calculate the ph of the solution. Sr(OH) 2 Sr OH x 0.20 M = M M M poh = Log[OH ] = 0.76 ph = poh = 13.24
18 "#$%&''()*+,)./) (5"6%)7"#)'1$)8359%) 1. The ph of 0.20 M HCN is Calculate the Ka for HCN. Compare your calculated value with that in the table. [H + ] = 10 ph = = M HCN H + + CN I 0.20 M 0 0 C M M M E M M Ka = ( ) 2 = 5.0 x Ka = 5.0 x The ph of 2.20 M HF is Calculate the Ka for HF. Compare your calculated value with that in the table. Ka = 3.5 x The ph of M CH 3 COOH is Calculate the Ka for CH 3 COOH. Compare your calculated value with that in the table. Ka = 1.8 x 10 5
19 4. The ph of 1.65 M H 3 BO 3 is Calculate the Ka for H 3 BO 3. Compare your calculated value with that in the table. Ka = 7.3 x The ph of a 0.10 M diprotic acid is 3.683, calculate the Ka and identify the acid. [H + ] = 10 ph = = M H 2 X H + + HX Note a diprotic weak acid only loses one proton. I 0.10 M 0 0 C M M M E M M Ka = ( ) 2 = 4.3 x Ka = 4.3 x 10 7 Carbonic acid H 2 CO 3 Look up on Ka Table. 6. The ph of 0.20 M NH 3 is ; calculate the Kb of the Base. poh = ph = [OH ] = 10 poh = M NH 3 + H 2 O NH OH I 0.20 M 0 0 C M M M E M M M Kb= ( ) 2 = 1.4 x 10 5
20 7. The ph of 0.40 M NaCN is ; calculate the ph for the basic salt. Start by writing an equation and an ICE chart. poh = ph = [OH ] = 10 poh = M CN + H 2 O HCN + OH I 0.40 M 0 0 C M M M E M M M Kb= ( ) 2 = 2.0 x The ph of a 0.10 M triprotic acid is 5.068, calculate the Ka and identify the acid. [H + ] = 10 ph = = 8.55 x 10 6 M H 3 X H + + H 2 X Note a triprotic weak acid only loses one proton. I 0.10 M 0 0 C 8.55 x 10 6 M 8.55 x 10 6 M 8.55 x 10 6 M E 0.10 M 8.55 x 10 6 M 8.55 x 10 6 M Ka = (8.55 x 10 6 ) 2 = 7.3 x Ka = 7.3 x Boric acid H 3 BO 3 Look up on Ka Table.
21 9. How many grams of CH 3 COOH are dissolved in 2.00 L of a solution with ph = 2.45? [H + ] = = M CH 3 COOH H + + CH 3 COO I x 0 0 C M M M E x M M M Keq = [H + ][CH 3 COO ] [CH 3 COOH] 1.8 x 10 5 = ( )( ) [CH 3 COOH] [CH 3 COOH] = M 2.00 L x moles x 60.0 g = 84 g 1 L 1 mole
22 "#$%&''()*+,,).)/"#)'0$)10%'%) WS # 11 K b For Weak Bases Determine the K b for each weak base. Write the ionization reaction for each. Remember that K w = K a K b (the acid and base must be conjugates). Find the base on the right side of the acid table and use the K a values that correspond. Be careful with amphiprotic anions NaNO 2 (the basic ion is NO 2 ) Kb(NO 2 ) = Kw = 1.0 x Ka(HNO 2 ) 4.6 x 10 4 Kb = 2.2 x KCH 3 COO (the basic ion is CH 3 COO ) Kb = 5.6 x NaHCO 3 Kb = 2.3 x NH 3 Kb = 1.8 x NaCN Kb = 2.0 x Li 2 HPO 4 Kb = 1.6 x KH 2 PO 4 Kb = 1.3 x K 2 CO 3 Kb = 1.8 x 10 4
23 "#$%&''()*+,,).)/"#)'0$)10%'%) 9. Calculate the [H + ], [OH ], ph, and poh for 0.20 M H 2 CO 3. [H + ] = 2.9 x 10 4 M [OH ] = 3.4 x M ph = 3.53 poh = The ph of 0.20 M H 2 CO 3 is Calculate the Ka for H 2 CO 3. Compare your calculated value with that in the table. Ka = 4.4 x Calculate the [H + ], [OH ], ph, and poh for 0.10 M CH 3 COOH. [H + ] = 1.3 x 10 3 M [OH ] = 7.5 x M ph = 2.87 poh = The ph of 0.10 M CH 3 COOH is Calculate the Ka. [H + ] = = M CH 3 COOH H + + CH 3 COO I 0.10 M 0 0 C M M M E M M M Ka = [H + ][CH 3 COO ] [CH 3 COOH] Ka = ( )( ) ( ) Ka = 1.8 x 10 5
24 "#$%&''()*+,,).)/"#)'0$)10%'%) ml of M H 2 SO 4 reacts with ml of M NaOH. Calculate the ph of the resulting solution. H 2 SO 4 + 2NaOH Na 2 SO 4 + 2HOH L x mol = mol L x mol = mol L L I mole mole C mole mole E mole [OH ] = mole = M L poh = 1.88 ph = 12.12
25 "#$%&''()*+,)./01)231)42%')56)728/982(0"3%) For each weak bases calculate the [OH ], [H + ], poh and ph. Remember that you need to calculate Kb first M CN Kb(CN ) = Kw = 1.0 x = x 10 5 Ka(HCN) 4.9 x CN + H 2 O HCN + OH I C x x x E 0.20 x x x x 2 = x x x = [OH ] = 2.0 x 10 3 M [OH ] = 2.0 x 10 3 M poh = 2.69 ph = [H + ] = 4.9 x M M NaHS (the basic ion is HS ) Kb = 1.1 x 10 7 [OH ] = 3.3 x 10 5 M poh = 4.48 ph = 9.52 [H + ] = 3.0 x M M KCH 3 COO Kb = 5.55 x [OH ] = 6.1 x 10 6 M poh = 5.21 ph = 8.79 [H + ] = 1.6 x 10 9 M
26 ) M KHCO 3 Kb = 2.3 x 10 8 [OH ] = 9.6 x 10 5 M poh = 4.02 ph = 9.98 [H + ] = 1.0 x M M NH 3 Kb = x 10 5 [OH ] = 3.3 x 10 3 M poh = 2.49 ph = [H + ] = 3.1 x M 6. If the ph of a 0.10 M weak acid HX is 3.683, calculate the Ka for the acid and identify the acid using your acid chart. HX H + X I M 0 0 C E Ka = ( ) 2 = 4.3 x 10 7 Carbonic acid ( ) 7. Calculate the [H + ], [OH ], ph, and poh for 0.80 M H 3 BO 3. [H + ] = 2.4 x 10 5 M [OH ] = 4.1 x M ph = 4.62 poh = Calculate the [H + ], [OH ], ph, and poh for 0.25 M H 2 CO 3. [H + ] = 3.3 x 10 4 M [OH ] = 3.0 x M ph = 3.48 poh = 10.52
27 9. The ph of 1.65 M H 3 BO 3 is Calculate the Ka for H 3 BO 3. Compare your calculated value with that in the table. Ka = 7.3 x [OH ] = 2.88 x M ph = 4.46 [H + ] = 3.47 x 10 5 poh = 9.54 ) 10. The ph of 0.65 M NaX is Calculate the Kb for NaX. poh = = 1.54 [OH ] = = M CN + H 2 O HCN + OH I 0.65 M 0 0 C M M M E M M M Kb = ( ) 2 (0.6212) Kb = 1.3 x Consider the following reaction: 2HCl + Ba(OH) 2 BaCl 2 + 2H 2 O When 3.16g samples of Ba(OH) 2 were titrated to the equivalence point with an HCl solution, the following data was recorded. Trial Volume of HCl added # ml Reject # ml # ml Calculate the original [HCl] = 1.04M ml Average 2HCl + Ba(OH) 2 BaCl 2 + 2H 2 O L 3.16 g Molarity = 3.16 g Ba(OH) 2 x 1 mole x 2 moles HCl 171.3g 1 mole Ba(OH) L [HCl] = 1.04M
28 12. Calculate the volume of 0.200M H 2 SO 4 required to neutralize 25.0 ml of 0.100M NaOH. ) L ml of.200m HCl is mixed with 50.0 ml.100m NaOH, calculate the ph of the resulting solution. No excess ph = ml of 0.10M H 2 SO 4 is mixed with 25 ml 0.20M NaOH, calculate the ph of the resulting solution. ph = ml of.200m HCl is mixed with ml.100m NaOH, calculate the ph of the resulting solution. ph = Define standard solution and describe two ways to standardize a solution. A standard solution is one of known molarity. If you make the solution from a weighed amount of solid and dilute it to a final volume in a volumetric flask it is a standard solution. If you titrate a solution to determine its concentration it is a standard solution. 17. What is the [H 3 O + ] in a solution formed by adding 60.0 ml of water to 40.0 ml of M KOH solution? [H+] = 6.3 x M
29 1. Definition (buffer) A solution that is made by mixing a weak acid or base with a salt containing the conjugate which maintains a relatively constant ph. 2. Acid Conjugate Base Salt HCN CN NaCN H 2 CO 3 HCO 3 KHCO 3 + NH 4 NH 3 NH 4 Cl HF F NaF CH 3 COOH CH 3 COO NaCH 3 COO H 2 C 2 O 4 HC 2 O 4 Na HC 2 O 4 3. Write an equation for the first three buffer systems above. HCN H + + CN H 2 CO 3 H + + HCO 3 NH 3 + H 2 O NH OH 4. Which buffer could have a ph of 4.0? Which buffer could have a ph of 10.0?
30 a) HCl & NaCl b) HF & NaF c) NH 3 & NH 4 Cl 5. Predict how the buffer of ph = 9.00 will change. Your answers are 9.00, 8.98, 9.01, 2.00, and Final ph a) 2 drops of 0.10M HCl are added 8.98 b) 1 drop of 0.10M NaOH is added 9.01 c) 10 ml of 1.0 M HCl are added 2.00
31 6. Write an equation for the carbonic acid, sodium hydrogencarbonate buffer system. A few drops of HCl are added. Describe the shift and each concentration change. Equation: H 2 CO 3 H + + HCO 3 Shift left [H + ] = increases [H 2 CO 3 ] = increases [HCO 3 ] = decreases Indicators 1. Definition (Indicator) A weak acid whose conjugate base is a different color. 2. Equilibrium equation HInd H + + Ind 3. Colors for methyl orange HInd red Ind yellow 4. Compare the relative sizes of [HInd] and [Ind ] at the following ph s. Color Relationship ph = 2.0 red [Hind] > [Ind ] ph = 3.7 orange [Hind] = [Ind ] ph = 5.0 yellow [Hind] < [Ind ] 5. HCl is added to methyl orange, describe if each increases or decreases. [H + ] increases [HInd] [Ind ] Color Change increases decreases yellow to red 6. NaOH is added to methyl orange, describe if each increases or decreases. [H + ] decreases [HInd] decreases
32 [Ind ] Color Change increases red to yellow 7. State two equations that are true at the transition point of an indicator. [Hind] = [Ind ] Ka = [H + ] 8. What indicator has a Ka = 4 x 10 8 Neutral Red 9. What is the Ka for methyl orange. 2 x A solution is pink in phenolphthalein and colorless in thymolphthalein. What is the ph of the solution? ph = A solution is blue in bromothymol blue, red in phenol red, and yellow in thymol blue. What is the ph of the solution? ph = 8
33 "#$%&''()*+,)./(#0(/"1)23#4'%) Choose an indicator and describe the approximate ph of the equivalence point for each titration. Complete each reaction. ph Indicator 1. HCl + NaOH > 7 bromothymol blue 2. HF + RbOH > 9 phenolphthalein 3. HI + Ba(OH) 2 > 7 bromothymol blue 4. HCN + KOH > 9 phenolphthalein 5. HClO 4 + NH 3 > 5 bromocresol green 6. CH 3 COOH + LiOH > 9 phenolphthalein 7. Calculate the Ka of bromothymol blue. Ka = 2 x An indicator has a ka = 1 x 10 10, determine the indicator. Thymolphthalein 9. Calculate the Ka of methyl orange. Ka = 2 x An indicator has a ka = 6.3 x 10 13, determine the indicator. Indigo Carmine 11. Explain the difference between an equivalence point and a transition point. The equivalence point refers to endpoint of a titration (moles acid = moles base) and a transition point refers to when an indicator changes color. Draw a titration curve for each of the following. 12. Adding 100 ml 1.0 M NaOH to 50 ml 1.0 M HCl 13. Adding 100 ml 1.0 M NaOH to 50 ml 1.0 M HCN ph Volume of base added Volume of base added
34 ) 14. Adding 100 ml 0.10 M HCl to 50 ml 0.10M NH Adding 100 ml.10 M HCl to 50 ml 0.10 M NaOH ph ph Volume of base added Volume of base added
TOPIC 11: Acids and Bases ELECTROLYTES are substances that when dissolves in water conduct electricity. They conduct electricity because they will break apart into Ex. NaCl(s)! Na + (aq) + Cl - (aq), and
Acids and Bases Chapter 16 The Arrhenius Model An acid is any substance that produces hydrogen ions, H +, in an aqueous solution. Example: when hydrogen chloride gas is dissolved in water, the following
SCH3U- R.H.KING ACADEMY SOLUTION & ACID/BASE WORKSHEET Name: The importance of water - MAKING CONNECTION READING 1. Read P. 368-375, P. 382-387 & P. 429-436; P. 375 # 1-11 & P. 389 # 1,7,9,12,15; P. 436
General Chemistry II Jasperse Acid-Base Chemistry. Extra Practice Problems 1 General Types/Groups of problems: Conceptual Questions. Acids, Bases, and p1 K b and pk b, Base Strength, and using K b or p7-10
Chapter 17 Acids and Bases How are acids different from bases? Acid Physical properties Base Physical properties Tastes sour Tastes bitter Feels slippery or slimy Chemical properties Chemical properties
Acids and : A Brief Review Acids: taste sour and cause dyes to change color. : taste bitter and feel soapy. Arrhenius: acids increase [H ] bases increase [OH ] in solution. Arrhenius: acid base salt water.
Chapter 14 - Acids and Bases 14.1 The Nature of Acids and Bases A. Arrhenius Model 1. Acids produce hydrogen ions in aqueous solutions 2. Bases produce hydroxide ions in aqueous solutions B. Bronsted-Lowry
Topic 8 Acids and bases 6 hours Hydronium ion (H3O + ) = more stable form of hydrogen ion (H + ) H + + H2O H3O + 8.1 Theories of acids and bases 2 hours 1. Arrhenius H-X / M-OH ACID a substance that dissociates
Ch 14 Page 1 Chapter 14: Acids and Bases Properties of Acids Sour taste React with some metals Turns blue litmus paper red React with bases Some Common Acids HCl, hydrochloric acid H 2 SO 4, sulfuric acid
Chapter 16 Acid-Base Equilibria Learning goals and key skills: Understand the nature of the hydrated proton, represented as either H + (aq) or H 3 O + (aq) Define and identify Arrhenuis acids and bases.
Ch 15: Acids and Bases A c i d s a n d B a s e s C h 1 5 P a g e 1 Homework: Read Chapter 15 Work out sample/practice exercises in the sections, Bonus problems: 39, 41, 49, 63, 67, 83, 91, 95, 99, 107,
Chemical reaction = process during which original substances change to new substances, reactants turn to... The bonds of reactants... and new bonds are... The classification of reactions: 1. Classification
Chapter 15 Acids and Bases Fu-Yin Hsu Stomach Acid and Heartburn The cells that line your stomach produce hydrochloric acid. To kill unwanted bacteria To help break down food To activate enzymes that break
UNIT (6) ACIDS AND BASES 6.1 Arrhenius Definition of Acids and Bases Definitions for acids and bases were proposed by the Swedish chemist Savante Arrhenius in 1884. Acids were defined as compounds that
Chapter 8 Acids and Bases Definitions Arrhenius definitions: An acid is a substance that produces H + (H 3 O + ) Ions in aqueous solution. A base is a substance that produces OH - ions in aqueous solution.
CHAPTER 12 Acids and Bases Opening Essay Formerly there were rather campy science-fiction television shows in which the hero was always being threatened with death by being plunged into a vat of boiling
4. Acid Base Chemistry 4.1. Terminology: 4.1.1. Bronsted / Lowry Acid: "An acid is a substance which can donate a hydrogen ion (H+) or a proton, while a base is a substance that accepts a proton. B + HA
Dr Mike Lyons School of Chemistry Trinity College Dublin. firstname.lastname@example.org ACID-BASE REACTIONS/ THE PH CONCEPT. Chemistry Preliminary Course 2011 1 Lecture topics. 2 lectures dealing with some core chemistry
Lecture Presentation Chapter 15 Acids and Bases Sherril Soman Grand Valley State University Stomach Acid and Heartburn The cells that line your stomach produce hydrochloric acid. To kill unwanted bacteria
Chapter 17 2) a) HCl and CH 3 COOH are both acids. A buffer must have an acid/base conjugate pair. b) NaH 2 PO 4 and Na 2 HPO 4 are an acid/base conjugate pair. They will make an excellent buffer. c) H
Balancing Chemical Equations Worksheet Intermediate Level Neutralization Reactions Salts are produced by the action of acids. Salts are written metal first, then non-metal. Eg. NaCl not ClNa Acid + Base
CAPTER Acids, Bases and Salts Properties of Aqueous Solutions of Acids and Bases Strong and Weak Acids Acids are substances that generate in aqueous solutions. Strong acids ionize 0% in water. That is,
Topic 5 5-1 Acid and Bases Acid and Bases 5-2 There are a number definitions for aicd and bases, depending on what is convenient to use in a particular situation: Arrhenius and Ostwald: Theory of electrolyte
Name: Class: Date: Chapter 13 & 14 Practice Exam Multiple Choice Identify the choice that best completes the statement or answers the question. 1. Acids generally release H 2 gas when they react with a.
University of Califnia, Davis F use with UC Davis Chem 8 and 118 Series Classification of Reagents in Chemistry I: Acids and Bases There are 3 definitions of acids and bases. All three are used in both
Acid-Base (Proton-Transfer) Reactions Chapter 17 An example of equilibrium: Acid base chemistry What are acids and bases? Every day descriptions Chemical description of acidic and basic solutions by Arrhenius
1. When the following equation is balanced, the coefficient of Al is. Al (s) + H 2 O (l)? Al(OH) (s) + H 2 (g) A) 1 B) 2 C) 4 D) 5 E) Al (s) + H 2 O (l)? Al(OH) (s) + H 2 (g) Al (s) + H 2 O (l)? Al(OH)
AP*Chemistry The Chemistry of Acids and Bases "ACID"--Latin word acidus, meaning sour. (lemon) "ALKALI"--Arabic word for the ashes that come from burning certain plants; water solutions feel slippery and
Acids and Bases Problem Set: Chapter 17 questions 5-7, 9, 11, 13, 18, 43, 67a-d, 71 Chapter 18 questions 5-9, 26, 27a-e, 32 Arrhenius Theory of Acids An acid base reaction involves the reaction of hydrogen
Chapter 9 Lecture Notes: Acids, Bases and Equilibrium Educational Goals 1. Given a chemical equation, write the law of mass action. 2. Given the equilibrium constant (K eq ) for a reaction, predict whether
Chemistry 3202 Unit 2 Acids and Bases Definitions of Acids and Bases An operational definition is one that is based on the observable properties, behaviours or uses of an entity. The earliest definitions
TYPES OF SOLUTIONS A solution is a homogeneous mixture of two substances: a solute and a solvent. Solute: substance being dissolved; present in lesser amount. Solvent: substance doing the dissolving; present
1. CONCENTRATION UNITS A solution is a homogeneous mixture of two or more chemical substances. If we have a solution made from a solid and a liquid, we say that the solid is dissolved in the liquid and
Chapter 16 Acid-Base Equilibria Most solutions that occur in nature are slightly acidic. One reason for this is that when carbon dioxide dissolves in water, it forms carbonic acid, H 2 CO 3. Basic solutions
ACID-BASE TITRATIONS 1 In this exercise you will use Excel to construct titration curves for a titration between a strong acid and strong base and between a weak acid and strong base. To set up a spreadsheet
Chapter 7 Answers and Solutions 7 Answers and Solutions to Text Problems 7.1 A mole is the amount of a substance that contains 6.02 x 10 23 items. For example, one mole of water contains 6.02 10 23 molecules
Chapter 7 Page 1 Chapter 7: Chemical Reactions A chemical reaction: a process in which at least one new substance is formed as the result of a chemical change. A + B C + D Reactants Products Evidence that
1 Experiment 7: Titration of an Antacid Objective: In this experiment, you will standardize a solution of base using the analytical technique known as titration. Using this standardized solution, you will
16.2 THE RØNSTED LOWRY ACID ASE CONCEPT Practice (Page 724) 1. (a) According to Arrhenius original theory, acids are substances that ionize in an aqueous solution, to produce aqueous hydrogen ions. (b)
Chapter 3 Formulas, Equations and Moles Interpreting Chemical Equations You can interpret a balanced chemical equation in many ways. On a microscopic level, two molecules of H 2 react with one molecule
CHEMISTRY 123-07 Midterm #1 Answer key October 14, 2010 Statistics: Average: 74 p (74%); Highest: 97 p (95%); Lowest: 33 p (33%) Number of students performing at or above average: 67 (57%) Number of students
Acids and Bases 7 Have You Ever Wondered? 1. Are all acids corrosive? 2. What is an amino acid? 3. Is vitamin C really an acid? Are all vitamins acids? 4. What is the difference between salt and sodium?
ACIDS AND BASES Mild acids and bases are used in cooking (their reaction makes biscuits and bread rise). Acids such as those in our stomachs eat away at food or digest it. Strong acids and bases are used
Acid-base Equilibria and Calculations A Chem1 Reference Text Stephen K. Lower Simon Fraser University Contents 1 Proton donor-acceptor equilibria 4 1.1 The ion product of water... 4 1.2 Acid and base strengths...
Name Writing and Balancing Chemical Equations Period When a substance undergoes a chemical reaction, chemical bonds are broken and new bonds are formed. This results in one or more new substances, often
SCH 4C1 Unit 2 Problem Set Questions taken from Frank Mustoe et all, "Chemistry 11", McGraw-Hill Ryerson, 2001 1. A small pin contains 0.0178 mol of iron. How many atoms of iron are in the pin? 2. A sample
Acid-base Equilibria and Calculations A Chem1 Reference Text Stephen K. Lower Simon Fraser University Contents 1 Proton donor-acceptor equilibria 4 1.1 The ion product of water... 4 1.2 Acid and base strengths...
Chemistry: Atoms First Julia Burdge & Jason Overby 9 Reactions in Aqueous s Chapter 9 Chemical Reactions in Aqueous s Kent L. McCorkle Cosumnes River College Sacramento, CA Copyright (c) The McGraw-Hill
Chemistry 201 Lecture 15 Practical aspects of buffers NC State University The everyday ph scale To review what ph means in practice, we consider the ph of everyday substances that we know from experience.
Chemical Principles As Applied to Soils I. Chemical units a. Moles and Avogadro s number The numbers of atoms, ions or molecules are important in chemical reactions because the number, rather than mass
Lesson Objectives Students will: Create a physical representation of the autoionization of water using the water kit. Describe and produce a physical representation of the dissociation of a strong acid
Textbook pages 158 to 175 What are acids and bases, and how do they react? Before You Read Topic 2.4 Summary You may have heard the word acid used in your everyday life. List some things that this word
STOICHIOMETRY LEARNING OUTCOMES At the end of this unit students will be expected to: UNIT 1 THE MOLE AND MOLAR MASS define molar mass and perform mole-mass inter-conversions for pure substances explain
Moles, Molecules, and Grams Worksheet Answer Key 1) How many are there in 24 grams of FeF 3? 1.28 x 10 23 2) How many are there in 450 grams of Na 2 SO 4? 1.91 x 10 24 3) How many grams are there in 2.3
CHM 130LL: ph, Buffers, and Indicators Many substances can be classified as acidic or basic. Acidic substances contain hydrogen ions, H +, while basic substances contain hydroxide ions, OH. The relative
Tuesday, November 27, 2012 Expectations: Sit in assigned seat Get out Folder, Notebook, Periodic Table Have out: Spiral (notes), Learning Target Log (new) No Backpacks on tables Listen/Pay Attention Learning
Properties Chapter 13 Chapter 13: Chemical Reactions Chemical Homework: All questions Reactions the Multiple- Choice and the odd-numbered questions on Exercises sections at the end of the chapter. Properties
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GCSE Chemistry Making Salts Instructions and answers for teachers The Activity: Learning Outcomes: To be able to recall the names and chemical formulae for commonly used acids To understand how salts can
2P32 Principles of Inorganic Chemistry Dr. M. Pilkington Lecture 22 The Acid-Base Character of Oxides and Hydroxides in Aqueous Solution Oxides; acidic, basic, amphoteric Classification of oxides - oxide
Solubility of Salts - Ksp We now focus on another aqueous equilibrium system, slightly soluble salts. These salts have a Solubility Product Constant, K sp. (We saw this in 1B with the sodium tetraborate
John W. Moore Conrad L. Stanitski Peter C. Jurs http://academic.cengage.com/chemistry/moore Chapter 15 Acids and Bases Arrhenius Definition Arrhenius: any substance which ionizes in water to produce: Protons
Molar Mass Molar mass = Mass in grams of one mole of any element, numerically equal to its atomic weight Molar mass of molecules can be determined from the chemical formula and molar masses of elements
TITRATION: STANDARDIZATION OF A BASE AND ANALYSIS OF STOMACH ANTACID TABLETS 2009, 1996, 1973 by David A. Katz. All rights reserved. Reproduction permitted for education use provided original copyright
Oakland Schools Chemistry Resource Unit Acid Base Concepts Karen Doree South Lyon East High School South Lyon Community Schools 1 Content Statements: C5.7 Acid-Base Concepts Acids and bases are important
NAME PER DATE DUE ACTIVE LEARNING IN CEMISTRY EDUCATIN "ALICE" CAPTER 21 ACIDS AND BASES Behavior In Water 21-1 1997, A.J. Girondi NTICE F RIGTS All rights reserved. No part of this document may be reproduced
Chemistry 101 - H Acids and Bases This presentation was created by Professor Carl H. Snyder Chemistry Department University of Miami Coral Gables, FL 33124 CSnyder@miami.edu Chapter 10 - Acids and Bases
Return to Lab Menu Acids and Bases in Your House OBJECTIVES Isolate a natural acid-base indicator. Determine the acid-base properties of common household solutions. INTRODUCTION Acids and bases are among
Chemistry 13 NT The most difficult thing to understand is the income tax. Albert Einstein 1 Chem 13 NT Solubility and Complex-ion Equilibria Module 1 Solubility Equilibria The Solubility Product Constant
Acids and Bases. Brønsted acids are proton donors, and Brønsted bases are proton acceptors. Examples of Brønsted acids: HCl, HBr, H 2 SO 4, HOH, H 3 O +, + NH 4, NH 3, CH 3 CO 2 H, H CH 2 COCH 3, H C CH,
Moles Balanced chemical equations Molar ratios Mass Composition Empirical and Molecular Mass Predicting Quantities Equations Micro World atoms & molecules Macro World grams Atomic mass is the mass of an
Chapter 3 ATOMS AND MOLECULES Multiple Choice Questions 1. Which of the following correctly represents 360 g of water? (i) 2 moles of H 2 0 (ii) 20 moles of water (iii) 6.022 10 23 molecules of water (iv)