PreparED Study Materials
CHEM 139: General Chemistry
School: Western Carolina University
Number of Notes and Study Guides Available: 0
Videos
Lattice Energy: Always Positive; Hydration Energy: Always Negative
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In this video we clarify why lattice energy in solids is always a positive value due to the energy needed to separate ions making it an endothermic process. On the flip side hydration energy is always negative as it releases heat when ions dissolve in water making it an exothermic reaction. We use sodium chloride as a real-world example to illustrate these crucial thermodynamic concepts
Endothermic Rxn: Ba(OH)2·8H2O & NH4NO3 Heat Dynamics
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Explore the endothermic reaction between Ba(OH)2·8H2O and NH4NO3 observing its impact on surroundings like the freezing water. Discover why touching the beaker feels cold and learn about heat transfer in such chemical reactions. This video is an insightful demonstration of heat absorption in chemical reactions.
Lone Pair vs. Bonding Pair Electrons: Atomic Insights Unveiled
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Explore the atomic world and the crucial distinctions between lone pair and bonding pair electrons in this insightful video. Delve into the fundamental aspects of atomic structure, electron orbitals, and their roles in chemical bonding, reactivity, and molecule formation.
Calculating Silver Density from Weight and Water Displacement
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Learn how to find the density of silver using weight and water displacement. A step-by-step guide to a common laboratory technique.
Understanding Key Assumptions of Kinetic Molecular Theory in Detail!
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Dive into the Kinetic Molecular Theory of Matter understanding how atoms and molecules possess kinetic energy which we measure as temperature. Explore the five core assumptions including the constant random motion of gas particles and the relation between kinetic energy and temperature. Demystify the concepts of particle collisions intermolecular interactions and the universal behavior of gases at given temperatures
Synthesis, Decomposition Reactions, and Oxidation-Reduction
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We explore synthesis and decomposition reactions, showcasing examples like the formation of water and its breakdown into simpler substances. We also clarify that while many of these reactions are redox reactions involving electron transfer, some synthesis and decomposition reactions may not necessarily be redox reactions, as seen in specific examples.


