PreparED Study Materials
CH 490: Biochem Structure & Function
School: Portland State 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
Calculate a Building's Age Using Nickel-63 Decay
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The scenario involves an archaeologist analyzing iron in an old building containing nickel-63, which has a known half-life of 92 years. With only 0.78% of the original nickel-63 remaining, the goal is to estimate the year when this discovery was made. We delve into the calculations and principles of first-order decay reactions.
Classifying Substances: From Pure Elements to Mixtures Explained
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Classify substances into various categories: element compound homogeneous mixture and heterogeneous mixture. This video breaks down the fundamental distinctions between pure substances and mixtures illustrating with real-world examples like urine pure water a Snickers™ bar and soil. A concise guide for understanding the essence of material classification in chemistry.
Theoretical Yield of TiCl? for Various Reactant Quantities
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Explore how to calculate the theoretical yield of TiCl? in moles based on different initial quantities of reactants in the chemical equation Ti + 2 Cl? ? TiCl?.
Classify: (a) Mixture (b) Element (c) Mixture (d) Compound
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In this video, we classify substances as elements, compounds, or mixtures, with air and soy sauce as mixtures, iron as an element, and table salt as a compound.
Rutherford's Gold Foil: The Pivot to the Modern Nuclear Atom Model
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Discover Rutherford's pivotal Gold Foil Experiment and its impact on atomic theory. Unveil the discrepancies with the Plum Pudding Model. Grasp the birth of the nuclear atom model through unexpected alpha particle deflections.


















