PreparED Study Materials
CH 433: CH 433
School: North Carolina State University
Number of Notes and Study Guides Available: 4
Notes
Videos
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.
Moles of H in Samples: H?O, NH?, N?H?, C??H??
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Discover how to calculate the number of moles of hydrogen in different chemical samples, including H?O, NH?, N?H?, and C??H??.
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Calculating Percent Composition: Using Molecular Formulas & Atomic Mas
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Understand the process of calculating percent composition using the molecular formula. Grasp the methodology with compounds like C2H4O2, CH2O2, and more. Discover how atomic masses influence the mass percent of elements in various compounds.
Calculating MgO Mass from Oxygen Gas at STP
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In this video, the problem involves calculating the mass of magnesium oxide (MgO) produced when 14.8 liters of oxygen gas react with magnesium metal according to the chemical equation 2Mg + O2 -> 2MgO. The stoichiometric relationship is used to determine that 0.6607 moles of oxygen gas results in 1.3214 moles of MgO, with a final calculation yielding a mass of 53.25 grams of MgO formed during the reaction at Standard Temperature and Pressure (STP).
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.



















