Test2 Answers

45 and why would you choose those particular two you

Info iconThis preview shows page 1. Sign up to view the full content.

View Full Document Right Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: hose particular two (you must provide a fundamental explanation). This answer requires that you support your answer with evidence. Species pKa Molecular weight (g/mol) H3PO4 2.148 98.00 NaH2PO4 7.198 119.98 Na2HPO4 12.375 141.96 Na3PO4 -163.94 A buffer consists of a mixture of an acid and its conjugate base (species related by the loss of a single proton). In a good buffer, the pKa of the acid is within 1 unit of the desired pH so that the buffer will have sufficiently high capacity to resist changes in pH. The pKa closest to the desired pH of 7.45 is 7.198, belonging to the acid NaH2PO4. The buffer is therefore made from a mixture of that acid and its conjugate base, Na2HPO4, so that the equation below is operational: 7. [40 marks] You have created 1.00L of a buffer from 0.3001M of a monoprotic acid and 0.2999M of its conjugate base (pKb=10.0). The measured buffer pH is . You add 15.00mL of 0.1200M monobasic strong base to the buffer. What is the new pH? This starts as a buffer questio...
View Full Document

Ask a homework question - tutors are online