Conduction, transfer of heat or electricity through a substance, resulting from a difference in temperature between different parts of the substance, in the case of heat, or from a difference in electric potential, in the case of electricity. Since heat is energy associated with the motions of the particles making up the substance, it is transferred by such motions, shifting from regions of higher temperature, where the particles are more energetic, to regions of lower temperature. The rate of heat flow between two regions is proportional to the temperature difference between them and the heat conductivity of the substance. In solids, the molecules themselves are bound and contribute to conduction of heat mainly by vibrating against neighboring molecules; a more important mechanism, however, is the migration of energetic free electrons through the solid. Metals, which have a high free-electron density, are good conductors of heat, while nonmetals, such as wood or glass, have few free electrons and do not conduct as well. Especially poor conductors, such as asbestos, have been used as insulators to impede heat flow (see insulation). Liquids and gases have their molecules farther apart and are generally poor conductors of heat. Conduction of electricity consists of the flow of charges as a result of an electromotive force, or potential difference. The rate of flow, i.e., the electric current, is proportional to the potential difference and to the electrical conductivity of the substance, which in turn depends on the nature of the substance, its cross-sectional area, and its temperature. In solids, electric current consists of a flow of electrons; as in the case of heat conduction, metals are better conductors of electricity because of their greater free-electron density, while nonmetals, such as rubber, are poor conductors and may be used as electrical insulators, or dielectrics. Increasing the cross-sectional area of a given conductor will increase the current because more electrons will be available for conduction. Increasing the temperature will inhibit conduction in a metal because the increased thermal motions of the electrons will tend to interfere with their regular flow in an electric current; in a nonmetal, however, an increase in temperature improves conduction because it frees more electrons.
What did you write I don't understand
Answer:
it turns from an atom origrionally to an ion
Explanation:
lithium atoms contain 3 protrons and 3 electrons. When it loses an electron, it is now an ion with more positive protons than electrons, meaning it is no longer balanced and has a +1 charge that was originally cancelled out by the electron we lost
Answer: 1.0 M molecular sucrose (C₁₂H₂₂O₁₁).
Explanation:
1) The depression of the freezing point of a solvent when you add a solute is a colligative property.
2) Colligative properties are those physical properties of solutions that depends on the number of solute particles dissolved into the solution.
3) The relation between the number of solute particles and the depresson of the freezing point is proportional: the greater the number of solute particles the greater the freezing point depression.
4) You need to find the solution with the highest freezing point, this is the solution in which the freezing point decreased the least.
5) Then, that is the solution with least number of solute particles.
6) Since all the given solutions have the same molarity (1.0 M), you only have to deal with the possible ionization of the different solutes.
7) NaCl, CaBr₂, AlBr₃, and KCl are ionic compounds, so each unit of them will ionize into two, three, four, and two ions, respectively, while sucrose, being a covalent compound does not dissociate.
Then, 1.0 M solution of sucrose will have less solute particles than the others, and will exhitibit the lowest freezing point depression, meaning that it will have the highest freezing point of the given solutions.
