Aspirin (acetylsalicylic acid) can cause stomach bleeding. Only the acid form can cross the stomach lining. Determine the ratio of base to its conjugate acid when the stomach pH=2.00. Ka aspirin = 2.75x10-5
Use the Henderson-Hasslebalch equation:
pH = pKa + log (base/acid).
You will need pKa. That is -log Ka.
You know pH and you can calculate pKa. Solve for (acid/base) and that is the ratio you want.
Well, we're talking about stomach bleeding here, so this is seriously no laughing matter! But I'll do my best to help you out, with a side of humor.
To find the ratio of the base (aspirin) to its conjugate acid (acetylsalicylic acid) at a given pH, you need to use the Henderson-Hasselbalch equation.
pH = pKa + log([A-]/[HA])
In this case, [A-] represents the concentration of the base (aspirin) and [HA] represents the concentration of the conjugate acid (acetylsalicylic acid).
First, let's find the pKa from the given Ka value:
pKa = -log(Ka) = -log(2.75x10^-5)
Now, let's substitute the given pH value of 2.00 and the pKa value into the equation:
2.00 = pKa + log([A-]/[HA])
Rearranging the equation, we get:
log([A-]/[HA]) = 2 - pKa
Now, we'll solve for the ratio of [A-]/[HA]:
[A-]/[HA] = 10^(2-pKa)
Plug in the pKa value and calculate:
[A-]/[HA] = 10^(2 - (-log(2.75x10^-5)))
[A-]/[HA] = 10^(2 + 4.56)
[A-]/[HA] = 10^6.56
[A-]/[HA] = 3.72 x 10^6
So, the ratio of base to its conjugate acid when the stomach pH is 2.00 is approximately 3.72 x 10^6 to 1.
Remember, this is just a chemical calculation, but please remember to seek professional advice for any medical concerns to avoid any upset stomachs or acidity in your life!
To determine the ratio of base to its conjugate acid, you need to calculate the concentration of the acid and the base at a pH of 2.00.
The pH of a solution is related to the concentration of hydrogen ions (H+) in the solution by the equation:
pH = -log[H+]
To find the concentration of H+ at pH 2.00, we need to calculate it using the equation:
[H+] = 10^(-pH)
[H+] = 10^(-2.00)
[H+] = 0.01 M
Now, let's assume that the concentration of the base (B) is x M. The concentration of the acid (BH+) can be calculated using the acid dissociation constant (Ka) and the concentration of the base:
Ka = [BH+][OH-] / [B]
Since we are given the value of Ka (2.75x10^-5), we can substitute the given values into the equation:
2.75x10^-5 = (x)(0.01) / (x)
Simplifying the equation:
2.75x10^-5 = 0.01 / x
x = 0.01 / 2.75x10^-5
x = 0.3636 M
Now, the ratio of the base (B) to its conjugate acid (BH+) is given by:
[BH+]/[B] = 0.3636 / 0.01
[BH+]/[B] = 36.36
Therefore, the ratio of the base to the conjugate acid when the stomach pH is 2.00 is approximately 36.36.
To determine the ratio of base to its conjugate acid when the stomach pH is 2.00, we need to calculate the concentration of base and its conjugate acid using the given pKa value.
The pKa value is a measure of how acidic a compound is. It indicates the tendency of a compound to lose a proton and become ionized.
The equation for the ionization of aspirin (acetylsalicylic acid) is as follows:
Aspirin (HA) ⇌ Acetylsalicylate ion (A-) + H+
The Ka value is derived from the equation:
Ka = [A-][H+]/[HA]
Given that the Ka value of aspirin is 2.75x10^-5, we can set up the equation as follows:
2.75x10^-5 = [A-][H+]/[HA]
Since the ratio of the base (A-) to the acid (HA) is unknown, we can define this ratio as x:1.
Therefore, the concentration of the aspirin is [HA] = 1 (since we assume it to be 1 M for simplicity).
The concentration of the acetylsalicylate ion, [A-], would then be "x" M.
The concentration of H+ is determined by the pH of the stomach, which is 2.00. In a solution, pH is the negative logarithm (base 10) of the hydrogen ion concentration [H+].
Therefore, the concentration of H+ can be calculated as [H+] = 10^(-pH).
For pH = 2.00, [H+] = 10^(-2) = 0.01 M.
Plugging these values back into the Ka equation, we get:
2.75x10^-5 = x * 0.01 / 1
Now, solving for x, we have:
x = (2.75x10^-5) / (0.01)
x ≈ 2.75x10^-3
Thus, the ratio of the base (acetylsalicylate ion) to its conjugate acid (aspirin) in the stomach when the pH is 2.00 is approximately 2.75x10^-3:1.