Explanation Given: The concentration of caffeine solution is 455 mg/L and p K b is 10.4 . Explanation: Caffeine is a weak base. The equation representing the dissociation of caffeine can be written as follows: C 8 H 10 N 4 O 2 ( a q ) + H 2 O ( l ) ⇄ C 8 H 10 N 4 O 2 H + ( a q ) + OH − ( a q ) The p K b is 10.4 . Solve for K b as follows: p K b = − log K b or K b = 10 − p K b Substitute p K b as 10.4 in the above expression as follows: K b = 10 − 10.4 = 3.98 × 10 − 11 Calculate the molarity of caffeine ( M ) as follows: M = w M w × 1 V Here, w is the given weight, M w is the molecular weight, and V is the volume. Substitute 455 × 10 − 3 g for w , 194.19 g/mol for M w , and 1 L for V to calculate molarity. M = 455 × 10 − 3 g 194.19 g/mol × 1 1 L = 0.0023 M Assume the concentration of [ OH − ] to be x . The ICE table can be written as follows: C 8 H 10 N 4 O 2 ( a q ) + H 2 O ( l ) → C 8 H 10 N 4 O 2 H + ( a q ) + OH − ( a q ) Initial 0

Masteringchemistry With Pearson Etext -- Valuepack Access Card -- For Principles Of Chemistry: A Molecular Approach

3rd Edition

ISBN: 9780133890686

Author: Tro

Publisher: PEARSON

See similar textbooks

Concept explainers

Ionic Equilibrium

Chemical equilibrium and ionic equilibrium are two major concepts in chemistry. Ionic equilibrium deals with the equilibrium involved in an ionization process while chemical equilibrium deals with the equilibrium during a chemical change. Ionic equilibri…

Arrhenius Acid

Arrhenius acid act as a good electrolyte as it dissociates to its respective ions in the aqueous solutions. Keeping it similar to the general acid properties, Arrhenius acid also neutralizes bases and turns litmus paper into red.

Bronsted Lowry Base In Inorganic Chemistry

Bronsted-Lowry base in inorganic chemistry is any chemical substance that can accept a proton from the other chemical substance it is reacting with.

Videos

Question

Chapter 15, Problem 91E

Interpretation Introduction

To determine: The pH of a solution containing caffeine.

Expert Solution & Answer

Want to see the full answer?

Check out a sample textbook solution

See solution

Chapter 15, Problem 90E

Chapter 15, Problem 92E

Students have asked these similar questions

Assign these C-NMR and H-NMR Spectrum

Predict the product of this organic reaction: IZ + HO i P+H₂O Specifically, in the drawing area below draw the skeletal ("line") structure of P. If there is no reasonable possibility for P, check the No answer box under the drawing area. No Answer Click and drag to start drawing a structure. ☐ :

Predict the products of this organic reaction: 0 O ----- A + KOH ? CH3-CH2-C-O-CH2-C-CH3 Specifically, in the drawing area below draw the condensed structure of the product, or products, of this reaction. (If there's more than one product, draw them in any arrangement you like, so long as they aren't touching.) If there aren't any products because this reaction won't happen, check the No reaction box under the drawing area. No reaction Click anywhere to draw the first atom of your structure. X ⑤ è

Chapter 15 Solutions

Masteringchemistry With Pearson Etext -- Valuepack Access Card -- For Principles Of Chemistry: A Molecular Approach

Ch. 15 - Prob. 1SAQ Ch. 15 - Q2. Which pair is a Brønsted–Lowry conjugate...Ch. 15 - Prob. 3SAQ Ch. 15 - Prob. 4SAQ Ch. 15 - Q5. An HNO3(aq) solution has a pH of 1.75. What is...Ch. 15 - Q6. Find the pH of a 0.350 M aqueous benzoic acid...Ch. 15 - Q7. Find the pH of a 0.155 M HClO2(aq) solution....Ch. 15 - Prob. 8SAQ Ch. 15 - Prob. 9SAQ Ch. 15 - Prob. 10SAQ

Ch. 15 - Prob. 11SAQ Ch. 15 - Prob. 12SAQ Ch. 15 - Prob. 13SAQ Ch. 15 - Prob. 14SAQ Ch. 15 - Q15. Which acid has the largest Ka: HClO2(aq),...Ch. 15 - 1. What causes heartburn? What are some possible...Ch. 15 - 2. What are the general physical and chemical...Ch. 15 - Prob. 3E Ch. 15 - Prob. 4E Ch. 15 - Prob. 5E Ch. 15 - Prob. 6E Ch. 15 - Prob. 7E Ch. 15 - Prob. 8E Ch. 15 - Prob. 9E Ch. 15 - Prob. 10E Ch. 15 - 11. What are diprotic and triprotic acids? List an...Ch. 15 - 12. Define the acid ionization constant and...Ch. 15 - 13. Write an equation for the autoionization of...Ch. 15 - 14. What happens to the [OH–] of a solution when...Ch. 15 - Prob. 15E Ch. 15 - Prob. 16E Ch. 15 - Prob. 17E Ch. 15 - Prob. 18E Ch. 15 - Prob. 19E Ch. 15 - Prob. 20E Ch. 15 - Prob. 21E Ch. 15 - 22. How can you determine if an anion will act as...Ch. 15 - 23. What is the relationship between the acid...Ch. 15 - 24. What kinds of cations act as weak acids? List...Ch. 15 - 25. When calculating the [H3O+] for a polyprotic...Ch. 15 - Prob. 26E Ch. 15 - Prob. 27E Ch. 15 - Prob. 28E Ch. 15 - Prob. 29E Ch. 15 - Prob. 30E Ch. 15 - 31. What is acid rain? What causes it, and where...Ch. 15 - Prob. 32E Ch. 15 - 33. Identify each substance as an acid or a base...Ch. 15 - 34. Identify each substance as an acid or a base...Ch. 15 - 35. In each reaction, identify the Brønsted–Lowry...Ch. 15 - Prob. 36E Ch. 15 - 37. Write the formula for the conjugate base of...Ch. 15 - 38. Write the formula for the conjugate acid of...Ch. 15 - 39. Both H2O and H2PO4– are amphoteric. Write an...Ch. 15 - 40. Both HCO3– and HS– are amphoteric. Write an...Ch. 15 - Prob. 41E Ch. 15 - Prob. 42E Ch. 15 - Prob. 43E Ch. 15 - Prob. 44E Ch. 15 - Prob. 45E Ch. 15 - Prob. 46E Ch. 15 - 47. Calculate [OH–] in each aqueous solution at 25...Ch. 15 - Prob. 48E Ch. 15 - Prob. 49E Ch. 15 - 50. Calculate [H3O+] and [OH–] for each solution...Ch. 15 - Prob. 51E Ch. 15 - Prob. 52E Ch. 15 - 53. Like all equilibrium constants, the value of...Ch. 15 - Prob. 54E Ch. 15 - 55. Calculate the pH of each acid solution....Ch. 15 - Prob. 56E Ch. 15 - Prob. 57E Ch. 15 - 58. Determine the pH of each solution. a. 0.048 M...Ch. 15 - Prob. 59E Ch. 15 - Prob. 60E Ch. 15 - 61. What is the pH of a solution in which 224 mL...Ch. 15 - Prob. 62E Ch. 15 - Prob. 63E Ch. 15 - 64. Determine the [H3O+] and pH of a 0.200 M...Ch. 15 - 65. Determine the pH of an HNO2 solution of each...Ch. 15 - 66. Determine the pH of an HF solution of each...Ch. 15 - Prob. 67E Ch. 15 - Prob. 68E Ch. 15 - Prob. 69E Ch. 15 - Prob. 70E Ch. 15 - 71. Determine the percent ionization of a 0.125 M...Ch. 15 - Prob. 72E Ch. 15 - Prob. 73E Ch. 15 - Prob. 74E Ch. 15 - Prob. 75E Ch. 15 - Prob. 76E Ch. 15 - Prob. 77E Ch. 15 - Prob. 78E Ch. 15 - Prob. 79E Ch. 15 - Prob. 80E Ch. 15 - Prob. 81E Ch. 15 - Prob. 82E Ch. 15 - Prob. 83E Ch. 15 - Prob. 84E Ch. 15 - Prob. 85E Ch. 15 - Prob. 86E Ch. 15 - Prob. 87E Ch. 15 - Prob. 88E Ch. 15 - Prob. 89E Ch. 15 - Prob. 90E Ch. 15 - Prob. 91E Ch. 15 - Prob. 92E Ch. 15 - Prob. 93E Ch. 15 - Prob. 94E Ch. 15 - Prob. 95E Ch. 15 - Prob. 96E Ch. 15 - 97. Determine the [OH–] and pH of a solution that...Ch. 15 - Prob. 98E Ch. 15 - Prob. 99E Ch. 15 - Prob. 100E Ch. 15 - Prob. 101E Ch. 15 - 102. Determine if each salt will form a solution...Ch. 15 - Prob. 103E Ch. 15 - Prob. 104E Ch. 15 - 105. Determine the pH of each solution. a. 0.10 M...Ch. 15 - 106. Determine the pH of each solution. a. 0.20 M...Ch. 15 - Prob. 107E Ch. 15 - Prob. 108E Ch. 15 - Prob. 109E Ch. 15 - Prob. 110E Ch. 15 - Prob. 111E Ch. 15 - 112. Calculate the [H3O+] and pH of each...Ch. 15 - 113. Calculate the concentration of all species in...Ch. 15 - 114. Calculate the concentration of all species in...Ch. 15 - 115. Calculate the [H3O+] and pH of each H2SO4...Ch. 15 - Prob. 116E Ch. 15 - Prob. 117E Ch. 15 - Prob. 118E Ch. 15 - 119. Based on their molecular structure, pick the...Ch. 15 - Prob. 120E Ch. 15 - Prob. 121E Ch. 15 - 122. Which is a stronger base, PO43– or AsO43–?...Ch. 15 - 123. Classify each species as either a Lewis acid...Ch. 15 - 124. Classify each species as either a Lewis acid...Ch. 15 - Prob. 125E Ch. 15 - Prob. 126E Ch. 15 - Prob. 127E Ch. 15 - Prob. 128E Ch. 15 - Prob. 129E Ch. 15 - Prob. 130E Ch. 15 - Prob. 131E Ch. 15 - Prob. 132E Ch. 15 - 133. Acid rain over the Great Lakes has a pH of...Ch. 15 - 134. White wines tend to be more acidic than red...Ch. 15 - 135. Common aspirin is acetylsalicylic acid, which...Ch. 15 - Prob. 136E Ch. 15 - Prob. 137E Ch. 15 - Prob. 138E Ch. 15 - Prob. 139E Ch. 15 - 140. Determine the pH of each two-component...Ch. 15 - Prob. 141E Ch. 15 - Prob. 142E Ch. 15 - 143. The pH of a 1.00 M solution of urea, a weak...Ch. 15 - 144. A solution is prepared by dissolving 0.10 mol...Ch. 15 - 145. Lactic acid is a weak acid found in milk. Its...Ch. 15 - Prob. 146E Ch. 15 - Prob. 147E Ch. 15 - Prob. 148E Ch. 15 - Prob. 149E Ch. 15 - 150. To what volume should you dilute 1 L of a...Ch. 15 - Prob. 151E Ch. 15 - Prob. 152E Ch. 15 - 153. Calculate the pH of a solution prepared from...Ch. 15 - 154. To 1.0 L of a 0.30 M solution of HClO2 is...Ch. 15 - 155. A mixture of Na2CO3 and NaHCO3 has a mass of...Ch. 15 - 156. A mixture of NaCN and NaHSO4 consists of a...Ch. 15 - 157. Without doing any calculations, determine...Ch. 15 - 158. Without doing any calculations, determine...Ch. 15 - Prob. 159E

Knowledge Booster

Learn more about

Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, chemistry and related others by exploring similar questions and additional content below.