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1332c7f9-0891-421e-b468-df9af5406d68 Crush some salt crystals into a powder Summary Physical

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bd4da886-2334-42b4-924e-b7b87c2bde87 Electrical Work Summary Electric work is the energy supplied by an electric current. In thermochemistry, it refers to the energy transfer that occurs during an electrochemical reaction or when electrical energy is used to perform work. To understand electric work, let's consider an everyday example: charging a mobile phone. When you connect your phone to a charger, electrical energy flows from the power source to the phone's battery. This energy transfer allows the battery to store electrical energy, which can later be used to power the phone and perform various tasks. Similarly, when you plug in an electrical device such as a laptop or a blender, electric work is done to power the device and enable its functionality. The electrical energy supplied through the power cord allows the device to operate and perform the desired tasks. In thermochemistry, electric work is involved in various electrochemical processes. For instance, during electrolysis, an electric current is passed through a solution or molten compound, causing a chemical reaction to occur. This reaction is driven by the electric work performed, leading to the separation or deposition of substances. Consider the process of electroplating, where a thin layer of metal is deposited onto an object. By passing an electric current through a solution containing metal ions, the metal ions are reduced and form a solid metal layer on the object's surface. The electrical work is responsible for driving this electrochemical process. Electric work is also crucial in battery technology. When a battery is used to power a device, such as a flashlight or a remote control, electric work is done as the chemical reactions inside the battery generate an electric current. This current supplies the necessary energy for the device to function. In summary, electric work in thermochemistry refers to the energy transfer that occurs during electrochemical reactions or when electrical energy is used to perform work. Examples include charging a mobile phone, operating electrical devices, electrolysis, electroplating, and battery-powered devices. Understanding electric work helps explain the energy transformations involved in various electrochemical processes and the role of electrical energy in powering everyday devices.

954c117d-e016-46ec-b8f9-8626b8b88743 Rate determining step: is the slowest step in a reaction mechanism. Summary

2d94bff9-3e6b-40f7-a22d-f64c82383808 Physical properties of metals: shiny, ductile (pulled into wires), malleable (hammered into thin sheets), conduct electricity. Summary

321f9bcf-34b5-4b82-803f-7215e00967a2 Halogens: F2 (Z = 9), Cl2 (Z = 17), Br2 (Z = 35) and I2 (Z = 53). Summary

This is placeholder text. To change this content, double-click on the element and click Change Content. < Back Atoms, molecules and stoichiometry This is placeholder text. To change this content, double-click on the element and click Change Content. Chapter Summary Previous Next Learning Outcomes 🎯: Define and use terms such as relative atomic mass, isotopic mass, empirical formula, molecular formula, and the mole in terms of the Avogadro constant. Analyze and use mass spectra to calculate the relative atomic mass of an element. Calculate empirical and molecular formulas using combustion data or composition by mass. Write and construct balanced equations. Perform calculations involving the mole concept, reacting masses, volumes of gases, and volumes and concentrations of solutions. Deduce stoichiometric relationships from calculations involving reacting masses, volumes of gases, and volumes and concentrations of solutions. Relative Atomic Mass and the Mole 🧮: Relative atomic mass is the weighted average mass of naturally occurring atoms of an element on a scale where an atom of carbon-12 has a mass of exactly 12 units. The mole is a unit used to count the number of particles in a substance and is based on the Avogadro constant. Empirical and Molecular Formulas 📝: Empirical formulas show the simplest whole-number ratio of atoms in a compound. Molecular formulas show the total number of atoms of each element present in one molecule or one formula unit of the compound. Balancing Chemical Equations ⚖️: Chemical equations must be balanced to ensure that the number of atoms of each element on the reactants side is equal to the number on the products side.

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46b28dc1-97db-42e8-a04d-b46b94e24427 Potential energy diagram of an endothermic reaction. Summary

884019c8-d6c0-4fbb-9e3f-b51a155b155c Build a nucleus simulation Quiz simulation from here https://examprepnotes.com/nucleus-creator-simulation-quiz Simple Nucleus Creator Simulation Summary

249e4b5d-153c-4db5-b7ef-4e42d4ea12fe Types of Chemical Reactions and Solution Stoichiometry Balancing Redox Reactions Summary

28635ed8-b7be-4c89-a74d-130041f99cef Plateau Summary The flat horizontal section on a heating or cooling curve that represents a phase change occurring at a constant temperature.