40131 lution is given by its acid-ionization consfant, K or the generic weak aci

Question

40131 lution is given by its acid-ionization consfant, K or the generic weak acid, HA HA(aq) A--(aq) + H+ (aq) d the acid-ionization constant is given by company, Pharma-pill. As a research technician at Pharma-pill, you are told that X-281 is a monoprotic weak acid, but because of security concens, the actual chemical formula must remain top secret The company is interested in the drug's Ka value because only the dissociated form of the chemical is active in preventing cholesterol buildup in arteries ith H2O in solution is given by its base-ionization nstant, Kb. For the generic weak base, B To tind the pK, of X-281, you prepare a 0.085 M test solution of X-281 at 25.0 °C. The pH of the solution is determined to be 3.00. What is the pKa of X-2817 B(aq) + H 00)BH (ag)+OH (ag) nd the base-ionization constant is given by Express your answer numerically PKa

Explanation / Answer

Given: X-281 is a monoprotic weak acid, let it be HX

HX<-->H+ +X- (dissociation in solution)

pka=-logKa ......(1)

ka=[H+] [X-]/[HX]

pH=-log [H+]

So,[H+]=10^-pH=10^-3

At equilibrium, [H+]=[X-]=x=10^-3M=0.001M

[HX]=[HX](initial concentration)-x=0.085M-10^-3=0.085M-0.001M=0.084M

ka=(0.001M)(0.001M)/(0.084M)=1.190*10^-5

pka=-log ka=-log (1.190*10^-5 )=4.924=4.9

pka=4.9

Related Questions

Navigate

• Browse (All)
• Browse 4
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.