Textbook Question
Determine whether or not the mixing of each pair of solutions results in a buffer. e. 125.0 mL of 0.15 M NH3; 150.0 mL of 0.20 M NaOH
Ch.17 - Aqueous Ionic Equilibrium
Chapter 17, Problem 54e
Determine whether or not the mixing of each pair of solutions results in a buffer. e. 105.0 mL of 0.15 M CH3NH2; 95.0 mL of 0.10 M HCl
Verified step by step guidance1
Identify the components involved in the solution: CH₃NH₂ is a weak base and HCl is a strong acid.
Calculate the moles of CH₃NH₂ using the formula: moles = concentration (M) × volume (L).
Calculate the moles of HCl using the formula: moles = concentration (M) × volume (L).
Determine if the moles of HCl are less than, equal to, or greater than the moles of CH₃NH₂ to see if there is an excess of weak base or if the strong acid completely neutralizes the weak base.
Conclude whether a buffer is formed: A buffer is formed if there is a significant amount of weak base and its conjugate acid (formed from the reaction with the strong acid) present in the solution.
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Key Concepts
Here are the essential concepts you must grasp in order to answer the question correctly.
Buffer Solutions
A buffer solution is a system that resists changes in pH upon the addition of small amounts of acid or base. It typically consists of a weak acid and its conjugate base or a weak base and its conjugate acid. Buffers are crucial in maintaining stable pH levels in various chemical and biological processes.
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03:02
Buffer Solutions
Weak Bases and Their Conjugate Acids
In this scenario, CH3NH2 (methylamine) is a weak base, and when it reacts with HCl (a strong acid), it forms its conjugate acid, CH3NH3+. The presence of both the weak base and its conjugate acid is essential for the formation of a buffer solution, allowing the system to neutralize added acids or bases.
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01:46Conjugate Acid-Base Relationships
Stoichiometry of Acid-Base Reactions
Stoichiometry involves the calculation of reactants and products in chemical reactions. In this case, determining whether a buffer forms requires calculating the moles of CH3NH2 and HCl to see if they can coexist in a ratio that maintains the buffer capacity. Understanding the stoichiometric relationships helps predict the outcome of mixing these solutions.
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01:09Acid-Base Reaction
Related Practice
Textbook Question
Determine whether or not the mixing of each pair of solutions results in a buffer. a. 75.0 mL of 0.10 M HF; 55.0 mL of 0.15 M NaF b. 150.0 mL of 0.10 M HF; 135.0 mL of 0.175 M HCl d. 125.0 mL of 0.15 M CH3NH2; 120.0 mL of 0.25 M CH3NH3Cl
Textbook Question
Determine whether or not the mixing of each pair of solutions results in a buffer. c. 165.0 mL of 0.10 M HF; 135.0 mL of 0.050 M KOH
Textbook Question
Blood is buffered by carbonic acid and the bicarbonate ion. Normal blood plasma is 0.024 M in HCO3- and 0.0012 M H2CO3 (pKa1 for H2CO3 at body temperature is 6.1).
a. What is the pH of blood plasma?
Textbook Question
Blood is buffered by carbonic acid and the bicarbonate ion. Normal blood plasma is 0.024 M in HCO3- and 0.0012 M H2CO3 (pKa1 for H2CO3 at body temperature is 6.1).
c. Given the volume from part (b), what mass of NaOH can be neutralized before the pH rises above 7.8?