Which of the following systems could act as a buffer?
A. HCl/Cl-
B. NaOH/OH-
C. HSO4-/SO4-2
D. H3O+/OH-
E. All of the above
my guess is C because A and B are too strong, but I am unsure of D. Can someone explain how to think through this?
You need a weak acid and its salt OR a weak base and its salt to have a buffer. C is the only one that is a weak acid/salt. I place D in the same class as A and B.
Well, let's think this through together, but with a touch of humor, of course!
Imagine you're at a party, and you've accidentally spilled some punch all over your brand new glittery shoes. Oh no! What do you do now? You have two options: you could either scream in panic and run out of the party, or you could find a handy-dandy sponge to soak up the spill, saving your shoes and maintaining your cool composure.
In this analogy, the spilled punch is like an excess of acid or base in a solution, and the handy-dandy sponge is like a buffer system that can absorb or release protons (H+) to help maintain a stable pH. So, which of these systems can be your trusty buffer sponge?
A. HCl/Cl-: This is a strong acid and its conjugate base, making it really good at giving out protons, but not so great at absorbing them. It's like trying to use a flamethrower to clean up a tiny spill. Not the best choice!
B. NaOH/OH-: This is a strong base and its conjugate acid, so it's excellent at mopping up excess protons like a mop on a mission. However, in this case, we need a system that can handle both acids and bases, so the mop won't do.
C. HSO4-/SO4-2: Ah, here we have a weak acid (HSO4-) and its conjugate base (SO4-2). Together, they can either release or absorb protons, depending on the situation. It's like having a versatile all-purpose sponge that can handle both acidic and basic spills. This looks promising!
D. H3O+/OH-: This pair represents the hydronium ion (H3O+) and the hydroxide ion (OH-). While they can certainly be involved in acid-base reactions, they don't represent a specific buffer system. They're more like the individuals at the party who are adept at fixing up minor spills, but they don't bring their own sponge to the party.
So, based on our analogy and a hint of chemistry, the correct choice is indeed C. HSO4-/SO4-2 could be acting as a buffer system because it has both a weak acid and its conjugate base, allowing it to absorb or release protons as needed.
Party on, my friend, and may your spills be easily cleaned up by trusty buffers like HSO4-/SO4-2!
To determine which systems could act as a buffer, you need to understand the characteristics of a buffer solution. A buffer is a solution that can resist changes in its pH when acids or bases are added. Buffers are typically made up of a weak acid and its conjugate base or a weak base and its conjugate acid.
Let's analyze each option and determine if it can act as a buffer:
A. HCl/Cl-: This system consists of a strong acid (HCl) and its conjugate base (Cl-). Since HCl is a strong acid, it dissociates completely in water, and there is no buffering capacity. Therefore, this system does not act as a buffer.
B. NaOH/OH-: This system consists of a strong base (NaOH) and its conjugate acid (OH-). Like HCl, NaOH is a strong base and dissociates completely in water. Therefore, this system does not act as a buffer.
C. HSO4-/SO4-2: This system consists of a weak acid (HSO4-) and its conjugate base (SO4-2). Since weak acids only partially dissociate in water, they have the ability to accept or donate protons to maintain the pH of the solution. Therefore, this system can act as a buffer.
D. H3O+/OH-: This system consists of hydronium ions (H3O+, which is commonly referred to as H+) and hydroxide ions (OH-). This combination does not involve a weak acid and its conjugate base, so it does not meet the definition of a buffer. Therefore, this system does not act as a buffer.
Based on the analysis above, the correct answer is C. The system HSO4-/SO4-2 can act as a buffer.
To determine which of the systems listed could act as a buffer, we need to understand what a buffer is and what properties it should possess.
A buffer is a solution that resists changes in pH when small amounts of acid or base are added to it. It typically consists of a weak acid and its conjugate base or a weak base and its conjugate acid. Buffers are capable of maintaining a relatively constant pH even with the addition of small amounts of acid or base.
Now, let's analyze each of the systems mentioned:
A. HCl/Cl-: This system consists of hydrochloric acid (HCl) and its conjugate base, chloride ion (Cl-). HCl is a strong acid, meaning it completely dissociates in water, and thus, it does not act as a buffer.
B. NaOH/OH-: This system consists of sodium hydroxide (NaOH) and hydroxide ion (OH-). NaOH is a strong base, and it dissociates into Na+ and OH- ions completely. Hence, it does not act as a buffer.
C. HSO4-/SO4-2: This system contains hydrogen sulfate (HSO4-) and sulfate (SO4-2). HSO4- is the conjugate base of a weak acid, sulfuric acid (H2SO4). SO4-2 is the conjugate base of a strong acid (H2SO4). Therefore, this system can act as a buffer.
D. H3O+/OH-: This system consists of hydronium ion (H3O+) and hydroxide ion (OH-). H3O+ is acidic, and OH- is basic, so this system does not act as a buffer.
E. All of the above: Since options A and B do not contain a weak acid and its conjugate base or a weak base and its conjugate acid, they cannot act as buffers. Thus, option E would be incorrect.
Therefore, the correct answer is C. HSO4-/SO4-2, as it consists of a weak acid (HSO4-) and its conjugate base (SO4-2), making it suitable for buffering.