Acid-Base Chemistry in Aqueous Solutions

[User Name]

Homework Statement

What are the final hydrogen ion concentration and pH of of a solution obtained by mixing 400 mL of 0.2 M NaOH with 150 mL of 0.1 M H3PO4? pKa's are 2.12, 7.21, 12.32

Homework Equations

Henderson-Hasselbach: pH = pKa + log /[a]

The Attempt at a Solution

0.2 M * .400 L = .08 mol NaOH
0.1 M * .150 L = .015 mol H3PO4
.015 mol of NaOH will be converted into H2O.

.08 mol - .015 mol = .065 mol NaOH
.015 mol H3PO4

I'm not 100% sure what to do after this besides find the molarities and continue on in the same methods but with H2O and H2PO4 -?

Am I headed in the right direction?

 

[Borek]

Write THREE consecutive reaction equations that occur during phosphoric acid neutralization. Find out how far the neutralization goes (in terms of limiting reagents). After the neutralization ends, what acid and conjugate base pair is present? What concentrations of both?

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