{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Homework 6-solutions

# Homework 6-solutions - hernandez(ah29758 Homework 6...

This preview shows pages 1–2. Sign up to view the full content.

hernandez (ah29758) – Homework 6 – sutcliffe – (51045) 1 This print-out should have 17 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. This HW covers through the end of Chapter 7 and will be on Exam 3. 001 10.0points A diprotic acid H 2 A has values of K a1 = 1 . 0 × 10 - 6 and K a2 = 1 . 0 × 10 - 10 . What is the [A 2 - ] in a 0.10 M solution of H 2 A? 1. 3 . 2 × 10 - 4 M 2. 0.20 M 3. 0.10 M 4. 1 . 0 × 10 - 10 M correct 5. 3 . 2 × 10 - 6 M Explanation: 002 10.0points What is the pH of a 0.020 M solution of hydrosulfuric acid, a diprotic acid? K a1 = 1 . 1 × 10 - 7 K a2 = 1 . 0 × 10 - 14 1. 5.22 2. 7.84 3. 4.33 correct 4. 3.65 5. 4.69 6. 7.00 7. 9.67 Explanation: Solve using ONLY the 1st ionization. So this works like any other monoprotic acid where the assumption [H + ] = radicalbig (Conc)( K a1 ) is valid. 003 10.0points Which equation represents K a2 for sulfurous acid? 1. HSO - 3 (aq) + H 2 O( ) H 2 SO 3 (aq) + OH - (aq) 2. H 2 SO 3 (aq) + 2 H 2 O( ) SO 2 - 3 (aq) + 2 H 3 O + (aq) 3. HSO - 3 (aq) + H 2 O( ) SO 2 - 3 (aq) + H 3 O + (aq) correct 4. SO 2 - 3 (aq) + H 2 O( ) HSO - 3 (aq) + OH - (aq) 5. H 2 SO 3 (aq) + H 2 O( ) HSO - 3 (aq) + H 3 O + (aq) Explanation: 004 10.0points Oxalic acid is a relatively strong diprotic acid with K 1 = 5 . 3 × 10 - 2 and K 2 = 5 . 3 × 10 - 5 . What is the [HC 2 O - 4 ] concentration in an ox- alic acid solution that is 0.10 M? 1. 0.073 M 2. 5 . 3 × 10 - 5 3. 0.10 4. 0.051 M correct 5. 0.027 M Explanation: K 1 = 5.3 × 10 - 2 K 2 = 5.3 × 10 - 5 In this case, since we’re considering a solu- tion of H 2 C 2 O 4 and HC 2 O - 4 , we should use the expression for K 1 here: K 1 = [H + ] [HC 2 O 4 - ] [H 2 C 2 O 4 ]

This preview has intentionally blurred sections. Sign up to view the full version.

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

{[ snackBarMessage ]}

### Page1 / 4

Homework 6-solutions - hernandez(ah29758 Homework 6...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online