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: a) 1.97 grams of carbon disulfide will remain after 37.0 days.
b) 2.85 grams of carbon monosulfide will be formed after 37.0 days.
Explanation: The decomposition of carbon disulfide is given as:
at t=0 4.83g 0 0
at t=37 days 4.83 - x x x
here,
x = amount of utilised in the reaction
This reaction follows first order kinetics so the rate law equation is:
where, k = rate constant
t = time
= Initial mass of reactant
A = Final mass of reactant
a) For this, the value of
t = 370 days = 3196800 sec
= 4.83
A = 4.83-x
Putting values in the above equation, we get
x = 2.85g
Amount of remained after 37 days = 4.83 - x
= 1.97g
b) Amount of carbon monosulfide formed will be equal to "x" only which we have calculated in the previous part.
Amount of carbon monosulfide formed = 2.85g