A Level Chemistry Revision (Year 13) "Electrophilic Substitution in Benzene" @Freesciencelessons

Uploaded October 2023 | Updated September 2026, 3 days ago

You can find all my A Level Chemistry videos fully indexed at freesciencelessons.co.uk/a-level-revision-videos/a-level-chemistry

In this video, we look at electrophilic substitution in benzene. First we recap electrophilic addition in alkenes, using cyclohexene as an example. We then look at why benzene is unable to induce a dipole in a bromine molecule. Finally, we explore how benzene reacts with electrophiles by electrophilic substitution.

A Level Chemistry Revision (Year 13) Electrophilic Substitution in Benzene

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$A Level Biology Revision Cell Fractionation You can find all my A Level Biology videos fully indexed at https://www.freesciencelessons.co.uk/a-level-revision-videos/a-level-biology/ In this video, we look at how organelles are separated by cell fractionation. First we look at the roles of a homogeniser and buffer. We then look at the relative sizes of the different organelles. Finally, we explore how the organelles are fractionated by ultracentrifugation. Image credits: Pancreatic acinar cells https://commons.wikimedia.org/wiki/File:Pancreatic_acinar_cells TEM.jpg Louisa Howard, Public domain, via Wikimedia Commons Heart dissected Samuel Levy, CC BY 3.0 https://creativecommons.org/licenses/by/3.0, via Wikimedia Commons Homogeniser https://commons.wikimedia.org/wiki/File:Tissue_glass_teflon_Dounce_homogenizer-02.jpg Lilly_M, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons Centrifuge https://commons.wikimedia.org/wiki/File:Multipurpose_centrifuge.JPG Retama, CC BY-SA 4.0 https://creativecommons.org/licenses/by-sa/4.0, via Wikimedia Commons$

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