PreparED Study Materials
CHEM 490: CHEM 490
School: University of Massachusetts
Number of Notes and Study Guides Available: 2
Notes
Videos
Glassware Drying with Acetone: The Science Behind It
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This discussion delves into the use of acetone as a solvent for removing water from laboratory glassware, exploring the science behind its effectiveness and the role of hydrogen bonding in facilitating rapid evaporation.
Nickel(II) Nitrate Solution Composition Analysis
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In this analysis, we determine the composition of a solution prepared by dissolving 12.15g of nickel(II) nitrate in 175mL of water (density 1.00 g/mL). The mass percent of nickel(II) nitrate is found to be approximately 6.50%, and the mole fraction of nickel(II) ions in the solution is calculated as 0.00672.
Electrons in outer shell of: Potassium, Calcium, Aluminum
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This video explains the importance of the number of valence electrons in an element's chemical behavior and demonstrates how to determine the valence electrons for potassium, calcium, and aluminum based on their positions in the periodic table. Valence electrons dictate an element's reactivity with other elements, making this knowledge essential for understanding chemical reactions.
Boyle's Law Explained: From Compression to Pressure Calculation
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Learn the intricacies of Boyle's Law through an example involving isothermal compression of a perfect gas. Watch as we calculate the original pressure using the change in volume and final conditions. This tutorial simplifies complex gas laws for easy comprehension.
Comparing Masses: Analyzing Water, Ethanol, Chloroform & Balsa Wood
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Explore the relationship between mass, density, and volume using real-life examples, including water, ethanol, chloroform, and balsa wood. Learn the process of calculating mass and uncover which substance has the highest mass based on given conditions.
Protons reveal electron count in atoms. Which statement applies?
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In this video, we explore the information that knowledge of the number of protons in a neutral element's atom can provide. Options for determining neutron count, electron count, and identifying the element's name are examined, with a conclusion that it allows us to know both the number of electrons and the element's name.













