PreparED Study Materials
CHEM 138: Introductory Chemistry
School: University of Illinois
Number of Notes and Study Guides Available: 0
Videos
Specific Rotation Calculation: Polarimeter Demystified
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Discover how to calculate specific rotations of samples using a polarimeter in this informative chemistry tutorial. Explore optical activity and learn step-by-step calculations for two real-world examples. Enhance your understanding of specific rotation and its application in chemical analysis.
Drawing the Lewis Structure for Glycine: The Protein Building Block
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Discover how amino acids, specifically glycine, form the foundation of proteins. Understand and visualize the Lewis structure representation of glycine. Grasp the significance of atomic bonding and electron distribution.
BrF?, ClF?, & IF? Lewis Structures: Which Don't Obey Octet Rule?
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Unravel the Lewis structures of BrF?, ClF?, and IF? and their relationship with the octet rule. Examine how fluorine bonds with bromine, chlorine, and iodine. Identify molecules that deviate from the standard octet distribution.
Identifying Incorrect Ground-State Electron Configurations and Providi
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This video delves into the significance of electron configurations in understanding an atom's chemical behavior. It examines and corrects inaccuracies in the electron configurations of Aluminium (Al), Boron (B), and Fluorine (F). For instance, the electron configuration for Aluminium is initially presented with an incorrect number of electrons in the 2p subshell, stressing the importance of adhering to the rules of electron configuration for precise atomic representation.
Ionic Character Comparison: Analyzing NaBr vs. HBr and BrCl vs. FCl
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Discover the analysis of ionic character in compounds based on electronegativity differences. Learn about the contrasts between NaBr vs. HBr and BrCl vs. FCl. Grasp why NaBr and FCl showcase greater ionic character than their paired compounds.
Why geometric isomerism is not possible in alkynes
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This video provides insights into the concept of geometric isomerism in organic chemistry and explains why alkynes, which contain carbon-carbon triple bonds and adopt a linear structure, cannot exhibit this form of isomerism, unlike alkenes with double bonds that restrict rotation.


















