{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

Substance conducting only a slight electric current

Info icon This preview shows pages 17–20. Sign up to view the full content.

View Full Document Right Arrow Icon
substance conducting only a slight electric current at room temp but showing increased  conductivity at higher temp conductivity at lower temp can be achieved if the substance is doped with other  elements ex when silicon is replaced by arsenic atms, each having 1 more valence elctron than  silicon, extra electrons become available for conduction n-type conductor conductivity increased by doping it with atoms having more valence electrons than the  atoms in the host crystal p-type conductor doped with atoms having fewer valence electrons than the host crystal has positive holes which are charge carriers p-n junction connection of p and n type
Image of page 17

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

View Full Document Right Arrow Icon
03:14 charge carriers of p-type region are holes, the n-type carry the electron 16.6 molecular solids 16.7 ionic solids stable, high-melting point substance held together by the strong electrostatic forces that  exist between oppositely charged ions charge ions (anions) packed in one of the closest packing arrangments (hcp or ccp) and  smaller cations fit into holes  three types of holes in closest packed trigonal holes (three spheres in same layer) tetrahedral holes (dimple in three spheres in an adjacent layer), r=0.225R octahedral holes (between 2 sets of three spheres in adjoining layers), r=0.414R small r=small atom’s radius, big R=larger atom’s radius 16.8 structures of actual ionic solids stoichiometry of the soild must be determined by the charges because it must be nuetral 16.9 Lattice defects 16.11 Phase diagram critical temp- temp at which the vapor can no longer be liquefied no matter what  pressure is applied criritcal pressure- pressure at which is required to procude liquification at critical temp critical point- point of critical temp and pressure liquid/vapor line on phase diagram ends at critical point for water
Image of page 18
03:14 Chapter 17:Properties of Solutions 17.1 Solution Composition solute- substance being dissolved solvent- substance dissolving the medium when liquids are mixed, the liquid present in the largest amount mass percent- percent solute by mass grams of solute/grams of solution * 100% in very dilute aqueas solutions the Molality and Molarity are nearly the same mole fraction of a component A= Xa = na/(na+nb) using moles or grams Molality= moles of solute/kg of solvent 17.2 thermodynamics of solution formation like dissolves like how to assume liquidity break up solute into individual components overcoming intermolecular forces in solvent to make room for solute allowing solute and solvent to interact to form the solution enthalpy (heat) of solution, Hdelta the overall enthalpy change associated with the formation of the solution positive (energy absorbed) negative (energy released) enthalpy of hydration (heat), Hdelta(hyd)
Image of page 19

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

View Full Document Right Arrow Icon
Image of page 20
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

What students are saying

  • Left Quote Icon

    As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

    Student Picture

    Kiran Temple University Fox School of Business ‘17, Course Hero Intern

  • Left Quote Icon

    I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

    Student Picture

    Dana University of Pennsylvania ‘17, Course Hero Intern

  • Left Quote Icon

    The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

    Student Picture

    Jill Tulane University ‘16, Course Hero Intern