Question: TRIS is a weak base. Compute pH of a solution containing .050 moles of TRIS and .020 moles of HCl in a total volume of 2L. pK(adsbygoogle = window.adsbygoogle || []).push({}); _{b}for TRIS is 5.92. Use RNH_{2}to represent TRIS.

Equation: pH = pKa+ log ([conjugate base]/[acid])

Work:

change equation for pOH:

pH = 14-pOH

pOH = pKb + log ([conjugate acid]/[base])

pOH = 5.02 + log (.010/.025) <---- I converted to mol/L for these values

pOH = 5.52

pH = 8.48

Real Answer: 8.26

Can someone show me where I went wrong? Thanks!

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# Weak base/ Strong acid pH

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