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explain what part of a buffer system is reacting when a strong base is added. does H2CO3 or Nahco3 react when a strong acid is added?

User Rhaskett
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Answer: H2CO3 reacts to a strong base and NaHCO3 reacts to a strong acid in a carbonic acid/bicarbonate buffer system.

When a strong base is added to a buffer solution, the buffer pair in the system reacts with the strong base to form the conjugate acid of the weak base. For example, in a carbonic acid/bicarbonate buffer system, when a strong base like NaOH is added, it reacts with the carbonic acid component of the system to form bicarbonate ion and water: H2CO3 + NaOH → NaHCO3 + H2O


The bicarbonate ion acts as a weak base that acts to neutralize the added strong base and maintains the pH of the solution. On the other hand, when a strong acid is added to the buffer solution, the buffer pair in the system reacts with the strong acid to form the conjugate base of the weak acid. For example, in the same carbonic acid/bicarbonate buffer system, when a strong acid like HCl is added, it reacts with the bicarbonate ion component of the system to form carbonic acid: NaHCO3 + HCl → NaCl + H2CO3


The carbonic acid acts as a weak acid that acts to neutralize the added strong acid and maintains the pH of the solution. So to answer your question, H2CO3 reacts to a strong base and NaHCO3 reacts to a strong acid in a carbonic acid/bicarbonate buffer system.

User Shyam Prasad
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Answer:

When a strong base is added to a buffer system, the weak acid component of the buffer system reacts to neutralize the base. For example, in the bicarbonate buffer system in blood, HCO3- acts as a weak acid and reacts with the strong base to form the conjugate base of the acid, CO32-.

When a strong acid is added to the bicarbonate buffer system, the bicarbonate acts as a base and reacts with the acid to form the conjugate acid of the base, H2CO3. So, in this case, it is H2CO3 that reacts to neutralize the strong acid, not NaHCO3

User Kimmax
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