PreparED Study Materials
CHEM 336: Organic Chemistry I
School: Northern Illinois 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
Positron Emission Nuclear Equations: Co-55, Na-22, F-18
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Learn how to write nuclear equations for positron emission with Co-55, Na-22, and F-18. Explore the fascinating world of nuclear reactions.
Volume of 49.8g HCl Gas at STP: Finding the Answer in Liters
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This video guides viewers through the process of calculating the volume occupied by Hydrochloric acid gas or HCl at standard temperature and pressure. Using the molar mass of HCl and its properties as an ideal gas the tutorial comprehensively explains each step to determine the volume from a given mass at STP. A must-watch for understanding gas volume conversions in chemistry
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).
Number of molecules in 3.5g H?O, 56.1g N?, 89g CCl?, 19g C?H??O?
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This video shows how to determine the number of molecules in a given sample by utilizing the concept of moles, Avogadro's number (6.022 x 10²³), and the molar mass of the substance. It provides step-by-step calculations for different substances, converting mass to the number of molecules and highlighting the versatile application of this approach.
Calculate oxygen molar concentration in water at 25°C with a partial p
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This video explores molar concentration (molarity) and demonstrates the calculation of oxygen's molar concentration in water at 25°C, considering a partial pressure of 0.22 atm by employing Henry's Law and the given Henry's Law constant for oxygen, revealing that under these conditions, there are 2.86 x 10?? moles of oxygen per liter of water, highlighting the significance of understanding these concepts for managing gas dissolution in liquids across varying circumstances.




