Homework 1 Solutions

Homework 1 Solutions - ENMA 300 Homework 1 Due: Monday,...

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

View Full Document Right Arrow Icon
ENMA 300 Homework 1 Due: Monday, Sept. 11, 2011 Note: You should get in the habit of showing your work even if you can solve a problem in your head. Reasoning is important and you need to show work to show your reasoning process. 1. Predict the type of bonding that holds the atoms/molecules together in the following solid materials. Explain why you have made the prediction for each material. Where appropriate include calculations. The Sargent-Welsh % ionic character table was used to calculate the % ionicity instead of the formula from the book. You will get similar values using equation in the book . It is important to calculate percent ionicity not just ∆EN. CaO: We need to do a % ionic character calculation for CaO. (∆EN=2.5 so %ionic bonding is ~ 79% from S-W table and equation 2.2). Thus, the bonding in CaO is highly ionic and we need to use ionic radii in any calculations. CdS: We need to do a % ionic character calculation for CdS. (∆EN=2.5 -1.7= 0.8, so %ionic bonding ~ 15% ). Thus, we would expect covalent bonding to be dominant and we need to use covalent radii (if you are using the table in the front of your text use the atomic radius) for any calculations. FeO: We need to do a % ionic character calculation for FeO. (∆EN=1.7 so %ionic bonding ~ 51%). Thus, we would expect ionic bonding to be dominant and we need to use ionic radii. However, it is covalent enough that we need to consider electronic as well as ionic conductivity if we are interested in electrical behavior. Bronze (a copper rich copper-tin alloy): Cu and Sn are both metals so we would expect the bonding to be metallic. Solid Ne
Background image of page 1

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

View Full DocumentRight Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/03/2012 for the course ENME 382 taught by Professor Christou during the Spring '12 term at Maryland.

Page1 / 3

Homework 1 Solutions - ENMA 300 Homework 1 Due: Monday,...

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

View Full Document Right Arrow Icon
Ask a homework question - tutors are online