Posted by Symone on Sunday, December 5, 2010 at 8:53pm.
Let's call aspirin, HA
HA ==> H^+ + A^-
Ka = (H^+)(A^-)/(HA)
(H^+) = x
(A^-) = x
(HA) = 500 mg x 2 tablets = 1000 mg (1 gram and moles is 1g/molar mass with M = mols/0.325L.
Solve for x and convert to pH.
so where does the Ka=3.3x10^-4 come in? and im lost with what you put in parethesis in ur explanation.
Note the FIRST equation I wrote has Ka. Substitute 3.3E-4 there.
Ka = (H^+)(A^-)/(HA)
(H^+) = x Let x = (H^+)
(A^-) = x then x = (A^-)
(HA) = 500 mg x 2 tablets = 1000 mg (1 gram and moles is 1g/molar mass with M = mols/0.325L.
You must substitute something for HA in the denominator of the Ka expression. The problem tells you that two (2) 500 mg tablets were placed in 325 mL solution. 2*500 mg = 1000 mg and that is 1.00 grams. How many moles is that. It is 1.00g/molar mass aspirin--you do the addition to find molar mass. Molarity is what goes into the equation, you have moles in 325 mL so that is moles/0.325L = (HA).
Solve for x and convert to pH.
does (HA)=58.695. my math was 1g/180.6 * 1/.325L
moles aspirin = 1.00g/180.16 = ??
M = moles/L = ??/0.325L = ??
x=2.37x10^-3
pH=2.63
is this correct?
Related Questions
AP CHEMISTRY - What is the of a solution obtained by dissolving two extra-...
Chemistry - What is the pH of a solution if two aspirin each containing 500mg of...
Chemistry - 1. Calculate the acetylsalicylic acid concentration (in mg/mL) of ...
chemistry - A 0.5130 g aspirin tablet which was dissolved in 95 percent ethanol ...
chem - quantitative determination of acetylsalicylic acid in aspirin tablets by ...
Chem - Aspirin (acetylsalicylic acid, ) is a weak monoprotic acid. To determine ...
chem - Aspirin, C9H8O4, is produced from salicylic acid, C7H6O3, and acetic ...
Chemistry - Aspirin is a weak acid with a Ka of 3.0x10^-5. Find the pH of a ...
chemistry - How many 400-mg aspirin tablets can be made from 40.0-kg of aspirin?
organic chemistry - Could you use NaOH to separate acetylsalicylic acid (aspirin...
For Further Reading
