15 Tutorial07-callister7e_Chapter17

# 15 Tutorial07-callister7e_Chapter17 - Callister chapter 17...

This preview shows pages 1–3. Sign up to view the full content.

SEM212 Semester one, 2006 1 Callister, chapter 17 Tutorial Notes 17.1: (a) Oxidation is the process by which an atom gives up an electron (or electrons) to become a cation. Reduction is the process by which an atom acquires an extra electron (or electrons) and becomes an anion. (b) Oxidation occurs at the anode; reduction at the cathode. Concept check 17.1: Iron would not corrode in water of high purity because all of the reduction reactions, Equations (17.3) through (17.7), depend on the presence of some impurity substance such as H + or M n+ ions or dissolved oxygen. 17.5: This problem calls for us to determine whether or not a voltage is generated in a Fe/Fe 2+ concentration cell, and, if so, its magnitude. Let us label the Fe cell having a 0.5 M Fe 2+ solution as cell 1, and the other as cell 2. Furthermore, assume that oxidation occurs within cell 2, wherein + 2 2 Fe = 10 -2 M. Hence, 1 + 2 2 + 2 1 2 Fe + Fe Fe + Fe and [ ] [] + + Δ 2 1 2 2 log 2 0592 . 0 = V Fe Fe V 0.0414 + = 5 . 0 10 log 2 0592 . 0 = 2 Therefore, a voltage of 0.0592 V is generated when oxidation occurs in the cell having the Zn 2+ concentration of 10 -2 M. 17.7 This problem asks for us to calculate the temperature for a zinc-lead electrochemical cell when the potential between the Zn and Pb electrodes is +0.568 V. On the basis of their relative positions in the standard emf series (Table 17.1), assume that Zn is oxidized and Pb is reduced. Thus, the electrochemical reaction that occurs within this cell is just Pb 2+ + Zn Pb + Zn 2+

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

View Full Document
SEM212 Semester one, 2006 2 Thus, Equation (17.20) is written in the form () ] [ ] [ ln V V = V 2 1 1 2 + + Δ n n
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

### Page1 / 4

15 Tutorial07-callister7e_Chapter17 - Callister chapter 17...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online