Answer:
-12162.47 joules (or -12000 joules when accounting for significant figures)
Explanation (btw I used 1 cal as 4.184 joules because SI units are better):
q = m c delta T
q = (70.9) (4.184) (25 - 66)
q = (70.9) (4.184) (-41)
q = -12162.47 joules
Answer is: pH value of solution of NaC₂H₃O₂ is 9.07.
Chemical reaction: C₂H₃O₂⁻ + H₂O ⇄ HC₂H₃O₂ + OH⁻.
Ka(HC₂H₃O₂) = 1,8·10⁻⁵.<span>
Ka · Kb = Kw.
</span>1,8·10⁻⁵ mol/dm³ · Kb = 1·10⁻¹⁴ mol²/dm⁶; the ionic product of water at 25°C.<span>
Kb(</span>C₂H₃O₂⁻)
= 1·10⁻¹⁴ mol²/dm⁶ ÷ 1,8·10⁻⁵ mol/dm³.<span>
Kb(</span>C₂H₃O₂⁻) =
5,56·10⁻¹⁰ mol/dm³.
c(C₂H₃O₂⁻) = 0,25 M.
[OH⁻] = [HC₂H₃O₂] = x.
[C₂H₃O₂⁻] = 0,25 M - x.
Kb = [OH⁻] · [HC₂H₃O₂] / [C₂H₃O₂⁻].
5,56·10⁻¹⁰ = x² / (0,25 M -x).
Solve quadratic equation: x = [OH⁻] = 0,0000118 M.
pOH = -log[OH⁻] = -log(0,0000118M) = 4,93.
pH + pOH = 14.
pH = 14 - 4,93 = 9,07.
When a capacitor has a potential difference between the plates it is said to be Constant.
Both plates have different charge which signifies that one has higher potential than the other.
Therefore, when we join them in parallel, charge will flow from higher to lower. and it continued to flow until equilibrium (the entire process took only a few seconds), indicating that the potential remains constant.
To learn more about constant potential difference in capacitor visit:
brainly.com/question/3480856
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I’m pretty sure cooking an egg could be it
