<span>Energy transformation or energy conversion is the process of changing one form of energy to another. In physics, the term energy describes the capacity to produce certain changes within a system, without regards to limitations in transformation imposed.</span><span>
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First, we write out a balanced equation.
HA <--> H(+) + A(-)
Next, we create an ICE table
HA <--> H+ + A-
[]i 0.40M 0M 0M
Δ[] -x +x +x
[]f 0.40-x x x
Next, we write out the Ka expression.
Ka = [H+][A-]/[HA]
Ka = x*x/(0.40-x)
However, because Ka is less than 10^-3, we can assume the amount of dissociation is negligible. Thus,
Assume 0.40-x ≈ 0.40
Therefore, 1.2x10^-6 = x^2/0.40
Then we solve for the [H+] concentration, or x

x=6.93x10^-4
Next, to find pH we do
pH = -log[H+]
pH = -log[6.93x10^-4]
pH = 3.2
A.) The reaction is Exothermic
<u>We are given:</u>
Volume of gas = 3.8 L
Pressure = 460 mmHg
Temperature = 77°c = (77+273)K = 350K
<u>Converting the pressure to atm:</u>
Pressure(in atm) = Pressure(in mmHg) / 760
Pressure = 460/760 = 0.6 atm
<u>Finding the number of moles:</u>
using the ideal gas equation:
PV = nRT [where R is the universal gas constant]
<em>replacing the given values in this equation</em>
(0.6)(3.8) = n(0.082)(350)
n = (0.6*3.8)/(0.082*350)
n = 0.08 moles