PreparED Study Materials
CHEM 121: Chemistry 121H
School: University of Massachusetts
Number of Notes and Study Guides Available: 5
Notes
Videos
Lewis Structures with Atom Connections & Charges
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Learn how to create Lewis structures for various molecules and assign charges where needed. Understand the molecular connectivity and electron distribution.
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.
Molar Mass Calculation: Sr(OH)2 N2O3 NaClO3 Cr2O3 Explained!
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In this chemistry tutorial learn how to calculate the molar mass of various compounds using atomic masses from the periodic table. Discover the molar mass for compounds such as Strontium Hydroxide Dinitrogen Trioxide Sodium Chlorate and Chromium(III) Oxide. A concise guide to understanding molar masses and their real-world applications.
Calculating the Mass of CCl4: Using Density and Volume Insights
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Learn the method to calculate the mass of a substance using its density and volume. This video demonstrates the practical application of density in determining the mass of carbon tetrachloride (CCl4) from a given volume.
Drawing Lewis Structures for Potassium, Barium, Aluminum, and Bromine
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We explore Lewis structures, which depict atom bonding and lone electron pairs. We create Lewis structures for potassium, barium, aluminum, and bromine by using group numbers in the periodic table to determine their valence electrons.
Reaction Unveiled: From Nitrogen Dioxide & Hydrogen to Ammonia & Water
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Explore the intriguing reaction of gaseous Nitrogen Dioxide and Hydrogen, resulting in the formation of Ammonia and Water. Grasp the significance of balanced chemical equations in respecting the law of conservation of mass. Dive into the properties and characteristics of each involved compound.














