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  • Oxidation and reduction (Conventional definition) - Khan Academy
    If we are talking about losing or gaining electrons, are we talking about ion formation? What are the bonds in the products in those reactions? ionic or covalent? Oxygen can share electrons but there is a moment in the video you clarify an element (e g Na) is losing the electron to O Can oxidation-reduction reactions happen between two non
  • Khan Academy
    If you're seeing this message, it means we're having trouble loading external resources on our website If you're behind a web filter, please make sure that the domains * kastatic org and * kasandbox org are unblocked
  • Reactions at the benzylic position - Khan Academy
    Reactions that occur at the benzylic position are very important for synthesis problems So let's look at a few We'll start with the free radical bromination of alkyl benzenes And so here is my alkyl benzene, so a benzene ring, and I have an alkyl group attached to that So this is a carbon And on that carbon, this is the benzylic position
  • Khan Academy
    Electronegativity is a measure of how strongly an atom attracts electrons from another atom in a chemical bond and this value is governed by where the particular atom is located in the periodic table (francium is the least electronegative element while fluorine is the most electronegative)
  • Double replacement reactions - Khan Academy
    A precipitation reaction is when two aqueous ionic compounds form a new ionic compound that is not soluble in water One example is the reaction between lead (II) nitrate and potassium iodide Both compounds are white solids that can be dissolved in water to make clear, colorless solutions
  • Isotopes (video) | Atoms, isotopes, and ions | Khan Academy
    The sum of the number of neutrons and protons in an atom is called its mass number Isotopes can be represented in writing using isotope notation Isotopes are atoms of the same element with different numbers of neutrons
  • Khan Academy
    Yep, oxygen, and any other molecule or atoms we breathe in can become ions It’s simple to become an ion since all a neutral atom molecule has to do is gain or lose an electron If one of these airborne ions is breathed in, it’ll simply transfer its charge to atoms molecules inside our body
  • Khan Academy
    The fourth part of the theory states that a chemical reaction is a rearrangement of atoms Parts of the theory had to be modified based on the discovery of subatomic particles and isotopes Chemists ask questions


















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