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Acid/Base Practice. Pop Quiz!. Name 3 characteristics of both acids and bases. Describe what an indicator is and what we have used them for in this class. Calculate the pH of the following: [H+]=1.47 x 10 -4 M [OH-]=3.55 x 10 -6 M [OH-]= 4.2 x 10 -2 M [H+]= 1.78 x 10 -4 M. *.
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Pop Quiz! • Name 3 characteristics of both acids and bases. • Describe what an indicator is and what we have used them for in this class. • Calculate the pH of the following: • [H+]=1.47 x 10-4 M • [OH-]=3.55 x 10-6 M • [OH-]= 4.2 x 10-2 M • [H+]= 1.78 x 10-4 M *
Pop Quiz! • Calculate the [OH-] concentrations of the following: • pOH=7.3 • pOH= 6.32 • pH= 1.5 • Calculate the [H+] concentrations of the following: • pH= 3.45 • pOH=8.2 • pH= 6.1 * *
Pop Quiz! • Complete, balance and name the compounds in the following neutralization reactions • HCl + KOH • H2SO4 + NaOH *
Pop Quiz! • If it takes 54 mL of 0.1 M NaOH to neutralize 125 mL of an HCl solution, what is the concentration of the HCl? • If it takes 50 mL of 0.5 M KOH solution to completely neutralize 135 mL of sulfuric acid solution, what is the concentration of the sulfuric acid solution? *
ANSWERS! • Acids: • Sour taste • Corrosive • pH less than 7 Bases: • Bitter taste • Corrosive • pH greater than 7 • Slippery feel
ANSWERS! • Indicators turn color in a specific range of pH. We can use them in titrations to tell when an endpoint has been reached.
ANSWERS! 3. Calculate the pH a. [H+]=1.47 x 10-4 M -log[H+] = pH -log (1.47 x 10-4) =3.83
ANSWERS! • Calculate the pH • [OH-] =3.55 x 10-6 -log[OH-]=pOH pH + pOH = 14 pH= 14 – pOH -log(3.55x 10-6)= 5.45 14 – 5.45=8.55 EXTRA STEP!!!
ANSWERS! • Calculate the pH • [OH-] = 4.2 x 10-2 -log[OH-]=pOH pH + pOH = 14 pH= 14 – pOH -log(4.2 x 10-2)=1.4 14 –1.4= 12.6 EXTRA STEP!!!
ANSWERS! • Calculate the pH • [H+] = 1.78 x 10-4 -log[H+]=pH -log(1.78x 10-4) =3.75
ANSWERS! • Calculate [OH-] • pOH=7.3 [OH-]= 10-pOH 10-7.3= 5.0 x 10-8
ANSWERS! • Calculate [OH-] b. pOH= 6.32 [OH-]= 10-pOH 10-6.32 =4.79 x 10-7
ANSWERS! • Calculate [OH-] c. pH=1.5 pH + pOH =14 14 – pH = pOH [OH-] = 10-pOH 14 – 1.5 = 12.5 10-12.5= 3.2 x 10-13 EXTRA STEP!!!
ANSWERS! • Calculate [H+] • pH= 3.45 [H+]= 10-pH 10-3.45 =3.55 x 10-4
ANSWERS! • Calculate [H+] b. pOH= 8.2 pH + pOH =14 14 – pOH =pH [H+]= 10-pH 14 – 8.2= 5.8 10-5.8=1.6 x 10-6 EXTRA STEP!!!
ANSWERS! • Calculate [H+] c. pH= 6.1 [H+]= 10-pH 10-6.1=7.9 x 10-7
ANSWERS! • Complete, balance and name. a. HCl + KOH
ANSWERS! • Complete, balance and name. a. HCl + KOH KCl + H2O ALREADY BALANCED! HCl: KOH: KCl: H2O: HydrochloricAcid PotassiumHydroxide PotassiumChloride Water
ANSWERS! 6. Complete, balance and name compounds b. H2SO4 + NaOH
ANSWERS! 6. Complete, balance and name compounds b. H2SO4 + NaOH Na2SO4 + H2O
ANSWERS! 6. Complete, balance and name compounds b. H2SO4 + 2NaOH Na2SO4 + 2H2O BALANCED! H2SO4: NaOH: Na2SO4: H2O: Sulfuric Acid Sodium Hydroxide Sodium Sulfate Water
ANSWERS! 7. If it takes 54 mL of 0.1 M NaOH to neutralize 125 mL of an HCl solution, what is the concentration of the HCl? Step 1: Write and balance the neutralization reaction: HCl + NaOH NaCl + H2O
ANSWERS! 7. If it takes 54 mL of 0.1 M NaOH to neutralize 125 mL of an HCl solution, what is the concentration of the HCl? Step 2: Identify the known 54 mL of 0.1 M NaOH
ANSWERS! 7. If it takes 54 mL of 0.1 M NaOH to neutralize 125 mL of an HCl solution, what is the concentration of the HCl? Step 2: Identify the known 54 mL of 0.1 M NaOH
ANSWERS! 7. If it takes 54 mL of 0.1 M NaOH to neutralize 125 mL of an HCl solution, what is the concentration of the HCl? Step 3: Identify the number of moles of known using molarity and liters.
ANSWERS! 7. If it takes 54 mL of 0.1 M NaOH to neutralize 125 mL of an HCl solution, what is the concentration of the HCl? Step 4: Use the molar ratio to convert from known moles to unknown moles
ANSWERS! 7. If it takes 54 mL of 0.1 M NaOH to neutralize 125 mL of an HCl solution, what is the concentration of the HCl? Step 5: Calculate the concentration (M) of HCl using the volume given in the problem.
ANSWERS! 8. If it takes 50 mL of 0.5 M KOH solution to completely neutralize 135 mL of sulfuric acid solution, what is the concentration of the sulfuric acid solution? Step 1: Write and balance the neutralization reaction: H2SO4 + 2KOH K2SO4 + 2H2O
ANSWERS! 8. If it takes 50 mL of 0.5 M KOH solution to completely neutralize 135 mL of sulfuric acid solution, what is the concentration of the sulfuric acid solution? Step 2: Identify the known. 50 ml of 0.5 M KOH
ANSWERS! 8. If it takes 50 mL of 0.5 M KOH solution to completely neutralize 135 mL of sulfuric acid solution, what is the concentration of the sulfuric acid solution? Step 2: Identify the known. 50 ml of 0.5 M KOH
ANSWERS! 8. If it takes 50 mL of 0.5 M KOH solution to completely neutralize 135 mL of sulfuric acid solution, what is the concentration of the sulfuric acid solution? Step 3: Calculate the moles of the known using the volume (in Liters) and molarity.
ANSWERS! 8. If it takes 50 mL of 0.5 M KOH solution to completely neutralize 135 mL of sulfuric acid solution, what is the concentration of the sulfuric acid solution? Step 4: Use the molar ratio to convert from known moles to unknown moles
ANSWERS! 8. If it takes 50 mL of 0.5 M KOH solution to completely neutralize 135 mL of sulfuric acid solution, what is the concentration of the sulfuric acid solution? Step 5: Calculate the concentration (M) of HCl using the volume given in the problem.