PreparED Study Materials
CHEM 118: Introductory Chemistry
School: University of Illinois
Number of Notes and Study Guides Available: 1
Notes
Videos
Balancing Equations: From Lead Sulfide to Ammonia Reactions
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This video shows you how to balance equations from the reaction of lead(II) sulfide with hydrochloric acid to ammonia's interaction with oxygen. Understand the nuances of atom balancing and grasp the precise stoichiometric relationships.
Drawing Lewis Structures for Ionic Compounds: SrO Li2S CaI2 & RbF
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Explore the art of constructing Lewis dot structures for ionic compounds such as SrO Li2S CaI2 and RbF. Understand the electron transfer process by diving into each atom's valency and its role in compound formation. Unpack the intricacies of ionic interactions for a deeper chemistry insight.
Precipitation Reactions Explained: From Solution to Solid Formation
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Unravel the chemistry behind precipitation reactions and the creation of insoluble salts. Learn how aqueous ions interact to form solid precipitates, illustrated with examples like silver nitrate and sodium chloride. Understand their significance in fields from water treatment to qualitative analysis.
Determining Neutrons from Atomic & Mass Numbers: A Comprehensive Guide
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Understand the relationship between atomic number, mass number, and neutrons within atoms. This video breaks down the simple calculation to determine the number of neutrons for specific elements like Nickel, Uranium, Scandium, and Argon.
Calculating the Mass Percent Composition of Chloroform (CHCl?)
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In this video, we delve into the concept of percent composition by mass, exemplified through the compound chloroform (CHCl?), which was once employed as an inhalation anesthetic despite its associated toxicity. By calculating the percent composition for each element within the compound, we gain valuable insights into its composition and its potential effects on health and properties.
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.


















