# 《材料科学与工程基础》英文影印版习题及思考题及答案

《材料科学与工程基础》英文习题及思考题及答案 第二章 习题和思考题 Questions and Problems 2.6 Allowed values for the quantum numbers ofelectrons are as follows: The relationships between n and the shell designationsare noted in Table 2.1. Relative tothe subshells, l ＝0 corresponds to an s subshell l ＝1 corresponds to a p subshell l ＝2 corresponds to a d subshell l ＝3 corresponds to an f subshell For the K shell, the four quantum numbersfor each of the two electrons in the 1s state, inthe order of nlmlms , are 100(1/2 ) and 100(-1/2 ).Write the four quantum numbers for allof the electrons intheLandMshells, and notewhich correspond to the s, p, and d subshells. 2.7 Give the electron configurations for the followingions: Fe2+, Fe3+, Cu+, Ba2+, Br-, andS2-. 2.17 (a) Briefly cite the main differences betweenionic, covalent, and metallic bonding. (b) State the Pauli exclusion principle. 2.18 Offer an explanation as to why covalently bonded materials are generally less dense than ionically or metallically bonded ones. 2.19 Compute the percents ionic character of the interatomic bonds for the following compounds: TiO2 , ZnTe, CsCl, InSb, and MgCl2 . 2.21 Using Table 2.2, determine the number of covalent bonds that are possible for atoms of the following elements: germanium, phosphorus, selenium, and chlorine. 2.24 On the basis of the hydrogen bond, explain the anomalous behavior of water when it freezes. That is, why is there volume expansion upon solidification? 3.1 What is the difference between atomic structure and crystal structure? 3.2 What is the difference between a crystal structure and a crystal system? 3.4 Show for the body-centered cubic crystal structure that the unit cell edge length a and the atomic radius R are related through a =4R/√3. 3.6 Show that the atomic packing factor for BCC is 0.68. . 3.27* Show that the minimum cation-to-anion radius ratio for a coordination number of 6 is 0.414. Hint: Use the NaCl crystal structure (Figure 3.5), and assume that anions and cations are just touching along cube edges and across face diagonals. 3.48 Draw an orthorhombic unit cell, and within that cell a  direction and a (210) plane. 3.50 Here are unit cells for two hypothetical metals: (a) What are the indices for the directions indicated by the two vectors in sketch (a)? (b) What are the indices for the two planes drawn in sketch (b)? 3.51* following directions: Within a cubic unit cell, sketch the . 3.53 Determine the indices for the directions shown in the following cubic un