nucleus is made up of protons

nucleus is made up of protons - nucleus is made up of...

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nucleus is made up of protons, neutrons and electrons. proton mass = 1.67E-27kg proton chrg = +1.6E-19C neutron mass = 1.67E-27kg neutron chrg = 0C electron mass = 9.1E-31kg elecrton chrg = -1.6E-19C z is the atomic number and is equal to the number of protons. A is the atomic mass and is equal to the atomic number + neutrons. isotopes are atoms with the same number of protons but different number of neutrons. AMU = 1/12(mass of carbon isotope 12c) = 1.66E-27kg Na = 6.02E23 atom/mol 1AMU*Na = 1g/mol 4 quantum numbers 1)- n is the principal quantum number, the shell numbers n=1,2,3,4. . n=K,L,M,N for 1=K. .. 2)- l signifies subshell and is related to quantification of angular momentum, also gives shape. l=0,1. ..(n-1) l=s,p,d,f for 0=s. .. 3)- orientation of subshells me= (-l),(-l+1). .-1,0,1,2,+l (a total # of 2l+1values) 4)- ms spin momentum = -.5, +.5 principal quantum #, shell designation, subshell, #of states, e per subshell. 1,k,s,1,2 2,L,s,1,2 p,3,6 3,M,s,1,2 p,3,6 d,5,10 4,N,s,1,2 p,3,6 d,5,10 f,7,14 a-melting temp, large Eo (bonding energy_ results in high melting temperature. b-mechanical stiffness (electrostatic models) shape represents stiffness a very steep curve represents high stiffness, a shallow curve represents a flexible material. c-thermal expansion a steep and deep curve represents a low thermal expansion. transition incomplete d sub shell inert filled s an p 3s23p6 halogen one e- different from filling 2s2 2p5 alkaline earth s2 ; alkali single e- Fa = (z1e)(z2e)/[(4πξ ²)] r = (A/B)^[1/(1-n)] 4 quantum numbers are used to characterize the electronic states Atomic number gives total number of electrons in neutral atom In an electrically neutral atom the number of electrons is equal to the number of protons. Ionic bonding is found in metallic and non metallic elements. Atoms obtain stable configurations similar to that of the noble gases. Found at the extremes of the periodic table. Strong interaction between components, high melting points, electric insulators, have low thermal conductance, non-directional bonding. Bonds are generally strong 50 ▫ 1500 KJ/Mol Covalent bonding has stable configurations which are achieved by sharing electrons between neighboring atoms. Covalent bonds can be directional, have directional interatomic bonding. Covalently bonded materials are insulators with generally strong 50 kj/mol 1500 KJ/Mol bonds. Covalently bonded materials are less dense than metallic or ionically bonded ones because covalent bonds are directional in nature whereas metallic and ionic are not; when bonds are Structure of crystalline solids. Crystalline materials are formed when atoms are arranged in repeating array. Occurs in amorphous materials where there is no long range order. A lattice is a 3d array of points. The unit cell is a small group of atoms which by many of them in a repeated manner generates the entire crystalline structure.
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This note was uploaded on 01/22/2012 for the course ME 2733 taught by Professor Meng during the Fall '10 term at LSU.

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nucleus is made up of protons - nucleus is made up of...

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