Thermodynamic Processes and Refrigeration Cycle Components

Item 5: Thermodynamic Processes

  • Isothermal Process: The substance changes state without changing its thermodynamic temperature.
  • Isobaric Process: The substance changes state without changing its pressure.
  • Isochoric Process: The substance changes state without changing its specific volume.
  • Isenthalpic Process: The substance changes state without changing its heat (enthalpy).
  • Isentropic Process: The substance changes state without changing its entropy.
  • Adiabatic Process: A process in which no heat transfer
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Radical Reactions: Key Terms and Definitions

Terms for Chapter 10: Radical Reactions


Radical

(Sec 3.1A, 10.1, 10.6, 10.7): An uncharged, electron-deficient chemical species in which one or more of the valence shell orbitals contains an unpaired electron, such as the methyl radical, •CH3. Also called a free radical.


Homolysis

(Sec 3.1A, 10.1): The cleavage of a covalent bond so that each fragment departs with one of the electrons of the bond that joined them, which usually produces radicals. Also called homolytic cleavage.


Peroxide

(Sec 10.lA)

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Chemical Reactions and Processes: A Concise Overview

Chemical Equilibrium

The effect of a catalyst on a reaction mixture accelerates the reaction both directly and inversely. Equilibrium is reached more rapidly, but the catalyst does not change the amounts at equilibrium. Kc remains constant.

Factors affecting equilibrium (Le Chatelier’s principle):

  • If temperature increases, the equilibrium shifts towards the endothermic reaction.
  • If temperature decreases, the equilibrium shifts towards the exothermic reaction.

Acids and Bases

  1. Arrhenius theory does not
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Properties and Types of Metals and Alloys

Metals and Alloys

Metals and alloys are mineral materials composed of one or more metallic elements and may contain non-metallic elements in small proportions. If a material consists of a single chemical element, it is a pure metallic material. When it consists of more than one chemical element, it is an alloy.

Pure Metals

Pure metals are rarely obtained directly from nature. Isolating them from the minerals they contain requires complex transformation processes.

Properties:

  • High hardness.
  • Suitable for
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Key Chemistry Definitions: Elements, Compounds, and Laws

Key Chemistry Definitions

  • Pure Substance: Homogeneous matter that cannot be broken down through simple physicochemical processes.
  • Element: A pure substance that cannot be broken down into simpler substances.
  • Compound: A substance made of two or more different elements.
  • Chemical Formula: Expresses the qualitative and quantitative composition of a given substance. The number in subscript form indicates the number of atoms.
  • Ionic Species: A formula that takes a superscript indicating the net electrical
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Understanding Nuclear Reactions, Fission, and Radioactivity

Energy Diagrams and Reaction Types

Graph Analysis:

  • Product Energy: The product energy is represented by the middle value, approximately 30 kcal.
  • Reagent Energy: The reagent energy is below 20 kcal.
  • ΔH (Enthalpy Change): ΔH = Product Energy – Reagent Energy = 30 kcal – 20 kcal = 10 kcal. The reaction is exothermic, but the ΔH value is positive, which is unusual and may indicate an error in the data. Exothermic reactions typically have negative ΔH values.
  • Activation Energy (Ea): The activation energy
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