Answer:
HC₂H₃O₂/KC₂H₃O₂
Explanation:
Considering the Henderson- Hasselbalch equation for the calculation of the pH of the basic buffer solution as:
For a best pair, the pKa value must be equal to pH.
NH₃/NH₄Cl forms a basic buffer and cannot account for pH = 5
out of the acidic buffer given,
So, HF , Ka = 3.5 × 10⁻⁴ , So pKa = 3.46
HC₂H₃O₂ , Ka = 1.8 × 10⁻⁵ , So pKa = 4.77
<u>The best pair to show pH = 5 is HC₂H₃O₂/KC₂H₃O₂</u>
Answer: The given statement is TRUE.
Explanation:
An equilibrium reaction is one in which rate of forward reaction is equal to the rate of backward reaction.
Equilibrium constant is defined as the ratio of the product of the concentration of products to the product of the concentration of reactants each raised to their stochiometric coefficient.
For example for the given equilibrium reaction;
Thus the given statement that in calculating the equilibrium constant for a reaction, the coefficients of the chemical equation are used as exponents for the factors in the equilibrium expression is True.
Answer:
0.758 V.
Explanation:
Hello!
In this case, case when we include the effect of concentration on an electrochemical cell, we need to consider the Nerst equation at 25 °C:
Whereas n stands for the number of moles of transferred electrons and Q the reaction quotient relating the concentration of the oxidized species over the concentration of the reduced species. In such a way, we can write the undergoing half-reactions in the cell, considering the iron's one is reversed because it has the most positive standard potential so it tends to reduction:
It means that the concentration of the oxidized species is 0.002 M (that of nickel), that of the reduced species is 0.40 M and there are two moles of transferred electrons; therefore, the generated potential turns out:
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