Balanced chemical reaction: A + 5C ⇄ AC₅.
<span>[A] = 0.100 M; equilibrium concentration.
</span><span>[C] = 0.0380 M.
</span>[AC₅] = 0.100 M.
Kf = [AC₅] / ([A] · [C]⁵).
Kf = 0.100 M ÷ (0.100 M · (0.0380 M)⁵.
Kf = 12620658.54 = 1,26·10⁷.
<span>The formation constant can be calculated when </span>chemical equilibrium is reached, when the forward reaction rate is equal to the reverse reaction rate.
Answer: The answer is A, A new element or different atom formed from the original two.
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-<em>TanqR</em>
Answer:

Explanation:
When acetic acid solution and barium hydroxide solution react together to give an aqueous solution of barium acetate and water
The balanced chemical reaction will be given by

Henderson–Hasselbalch equation is given as,
pH = pKa + log [A⁻] / [HA]
-------- (1)
Solution:
Convert Ka into pKa,
pKa = -log Ka
pKa = -log 1.37 × 10⁻⁴
pKa = 3.863
Putting value of pKa and pH in eq.1,
4.29 = 3.863 + log [lactate] / [lactic acid]
Or,
log [lactate] / [lactic acid] = 4.29 - 3.863
log [lactate] / [lactic acid] = 0.427
Taking Anti log,
[lactate] / [lactic acid]
= 2.673
Result:
2.673 M
lactate salt when mixed with 1 M Lactic acid produces a buffer of pH = 4.29.