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Kemi – Undervisningsvideoer – Khan (Kahn) academy

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Atoms, compounds, and ions
Chemistry is the study of matter, and all matter is made up of atoms. We will learn about elements, atomic number and mass, isotopes, moles (chemistry moles, not the animal), and compounds.

Chemical reactions and stoichiometry
We are now going to delve into the heart of chemistry. We learn ways of representing molecules and how molecules react. To do this, we'll even think about "how many" of a molecule we have using a quantity called a "mole".

Electronic structure of atoms
So we know that all matter is made up of atoms, but what is an atom made out of? Chemists describe the structure of atoms using models. This section will cover the Bohr model, photoelectric effect, absorption and emission spectra, quantum numbers, and electron configurations.

Periodic table
A little more than a century ago, the chemist Dmitri Mendeleev published an early form of the periodic table, which organizes the known elements of our world. His method of classifying the elements was so useful that we still use it even today. We will learn to apply this elegant table to an understanding of atomic structure and properties, including periodic table trends.

Chemical bonds
Chemical bonds are the glue that hold molecules together. We will learn about the different kinds of bonds, ways chemists draw bonds and molecules, and how the type of chemical bonding affects the bulk properties of a material. We will cover electronegativity, Lewis dot structures, VSEPR, bond hybridization, and ionic, covalent, and metallic bonds.

Gases and kinetic molecular theory
Properties of gases can be modeled using some relatively simple equations, which we can relate to the behavior of individual gas molecules. We will learn about the ideal gas law, vapor pressure, partial pressure, and the Maxwell Boltzmann distribution.

States of matter and intermolecular forces
Have you ever wondered how some insects are able to "skate" on the surface of water? We will learn about how intermolecular forces make this possible. We will also cover liquids, solids, mixtures, and phase changes.

Chemical equilibrium
Many chemical reactions are reversible, and the forward and backward reactions can occur at the same time. When the rate of the forward reaction is equal to the rate of the backward reaction, we call that a dynamic equilibrium. We will learn how equilibrium can be described by the equilibrium constant K, and how different factors than can affect the chemical equilibrium.

Acids and bases
In this section we will be talking about the basics of acids and bases and how acid-base chemistry is related to equilibria. We will cover acid and base definitions, pH, acid-base equilibria, acid-base properties of salts, and the pH of salt solutions.

Buffers, titrations, and solubility equilibria
We can combine our knowledge of acids and bases, equilibrium, and neutralization reactions to understand buffers and titrations. Solubility equilibria will build on concepts from solubility, precipitation, and equilibrium.

Thermodynamics is the study of heat, "thermo," and work, "dynamics." We will be learning about energy transfer during chemical and physical changes, and how we can predict what kind of changes will occur. Concepts covered in this tutorial include the laws of thermodynamics, internal energy, heat, work, PV diagrams, enthalpy, Hess's law, entropy, and Gibbs free energy.

Redox reactions and electrochemistry
Oxidation and reduction reactions power your phone and make it possible for your body to use the oxygen you inhale. We will learn about oxidation states (numbers), oxidation-reduction (redox) reactions, galvanic/voltaic cells, electrolytic cells, cell potentials, and how electrochemistry is related to thermodynamics and equilibrium.

Chemists are often interested in how fast a reaction will occur, and what we can do to control the rate. The study of reaction rates is called kinetics, and we will learn about average reaction rate, rate laws, the Arrhenius equation, reaction mechanisms, catalysts, and spectrophotometry.

Nuclear chemistry
Nuclear chemistry and radioactivity can treat cancer and make your watch glow in the dark. We will learn about radioactive decay, nuclear stability, carbon dating, half-life, and what is happening on a subatomic level during a nuclear reaction.

Meet the chemistry professional
What can you do with chemistry skills? A lot of things, it turns out! Learn about the diversity of careers available to people interested in chemistry.

Community explanations
Calling great explainers of the world! Help us answer frequently asked chemistry questions by writing clear, deep, engaging explanations. Your explanation may even be selected for an article on Khan Academy (with full credit to you)!

Ask a chemist! (Archived)
Hi, my name is Yuki and I get really excited about chemistry. Do you have a question or comment that might be related to chemistry? Ask your question between July 30 and August 2, and I will try my best to answer it. Please feel free to join in the discussion and answer some questions too!

Structure and bonding
Dot structures, hybridization, bond-line structures, electronegativity, polarity, physical properties

Resonance and acid-base chemistry
Formal charges, oxidation states, oxidation-reduction reactions, resonance structures, acid-base chemistry

Alkanes, cycloalkanes, and functional groups
Naming alkanes and cycloalkanes, conformations of alkanes and cycloalkanes, functional groups

Chirality, stereoisomers, assigning configurations using the R,S system, optical activity, Fischer projections, diastereomers, meso compounds

Substitution and elimination reactions
SN1, SN2, E1, E2, nucleophiles, nucleophilicity, basicity

Alkenes and alkynes
naming alkenes and alkynes, reactions of alkenes and alkynes, synthesis

Alcohols, ethers, epoxides, sulfides
alcohols, ethers, epoxides, thiols, sulfides

Conjugated systems and pericyclic reactions
Conjugation (eventually), addition reactions of conjugated dienes (eventually), Diels-Alder reaction, electrocyclic reactions (eventually)

Aromatic compounds
aromatic compounds, naming derivatives of benzene, electrophilic aromatic substitution reactions

Aldehydes and ketones
nomenclature and reactions of aldehydes and ketones

Carboxylic acids and derivatives
naming carboxylic acids, formation of carboxylic acid derivatives

Alpha carbon chemistry
formation of enolate anions, aldol condensations

nomenclature and reactions of amines

IR, UV/Vis, and NMR Spectroscopy

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