SAMPLE EXERCISE 17.3 Calculating the pH of a Buffer What is the pH of a buffer t
ID: 1022032 • Letter: S
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SAMPLE EXERCISE 17.3 Calculating the pH of a Buffer What is the pH of a buffer that is 0.12 M in lactic acid [CH,CH(OH)COOH, or HC,H,O, and 0.10 M in sodium lactate [CH, CH(OH)COONa or NaC,H,Os? For lactic acid, K.-1.4 x 10 SOLUTION Analyze We are asked to calculate the pH of a buffer containing lactic acid (HC, H,O,) and its conjugate base, the lactate ion (C,H,O,). Pisa We will first determine the pH using the method described in Section 17.1. Because HC,H,O, is a weak electrolyte and NaC,H,Os is a strong electrolyte, the major species in solution are HC andGJ 1,0-The Na, ion is a spectator ion. The HC,Hs0/C,H,0 co njugate acid-base pair determines [H] and, thus, pH: [H] can be determined using the 03, Na", determined using the acid-dissociation equilibrium of lactic acid.Explanation / Answer
strong electrolytes are categorized mainly into three categories strong acid,strong base,and salts.salts can also be called as ionic compounds and strong bases are also ionic compounds.the principal component in solutions for strong electrolytes are ions.since they are all ions dissociation is taken to be 100%.if the acid is one of the seven strong acids or if the base ends in M(OH)n or if it is of the form M(Xn) then they are termed strong electrolytes.
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weak electrolytes are weak acids and weak bases.they partially dissociate(1-10%) and the principal component in solution is the unionized species itself.all other acids other than the strong seven are weak acids and if it has a nitrogen atom then it is a weak acid.
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NH3 (ammonia), C5H5N (pyridine), and several more, all containing "N"
since lactate ion has already 0.10 M concentration before lactic acid has dissociated then after dissociation if x part of the lacticacid has dissociated then concentration of lactate ion becomes 0.10+x
strong acids HCl, HBr, HI, HNO3, HClO3, HClO4, and H2SO4 strong bases NaOH, KOH, LiOH, Ba(OH)2, and Ca(OH)2 salts NaCl, KBr, MgCl2, etcRelated Questions
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