The first row of elements fits in period 6, after the element lanthanum (La). The second row of elements fits in period 7, after the element actinium (Ac). 

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4 0

4 years ago

Which of the following is a buffer system? Which of the following is a buffer system? H2CO3(aq) and KHCO3(aq) NaCl(aq) and NaOH(

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Answer:

Explanation:

A buffer is defined as an aqueous mixture of a weak acid and its conjugate base or vice versa.

In the systems:

H₂CO₃(aq) and KHCO₃(aq): Carbonic acid, H₂CO₃, is a weak acid that, in solution with its conjugate pair, HCO₃⁻ make a buffer system.

NaCl(aq) and NaOH(aq): NaCl is a salt and NaOH is a strong base. Thus, this system is not  a buffer system.

H₂O(l) and HCl(aq): Water is a solvent and HCl a strong acid. This is not a buffer system.

HCl(aq) and NaOH(aq): HCl is a strong acid and NaOH a strong base. This is not a buffer system.

NaCl(aq) and NaNO₃(aq): Both NaCl and NaNO₃ are salts and this system is not a buffer system.

3 0

3 years ago