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Balancing Chemical Equations
Students are introduced to the process of balancing chemical equations. First, they see that a chemical equation describes the chemical reaction that takes place when two elements are combined. In chemistry, that reaction must be written...
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Boiling Point Elevation and Freezing Point Depression, Chemistry
Have you ever wondered why cities in cold climates put salt on the roads to help keep ice from forming? In this chemistry video, Sal explains why the introduction of salt molecules suppresses, or delays, the formation of ice crystals...
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Heat of Formation, Thermodynamics, Chemistry
In this chemistry video, Sal takes a closer look at what happens to the change in enthalpy during a chemical reaction. He points out that, given constant pressure, the enthalpy change becomes the heat added to the system at that constant...
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Introduction to Exponential Decay
Sal goes further into the decay of atoms by introducing the concept of Exponential Decay. He explains that when you have any decaying element, it can be described as the amount of the element present times e to a constant, such as...
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Carnot Cycle and Carnot Engine, Thermodynamics, Physics
The Carnot Cycle is the focus of this chemistry video. Carnot was a French engineer who proved that energy transfers happen in a cycle. They start and finish at the same pressure, volume, and temperature. A system that completes the...
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Carbon 14 Dating 1, Life on Earth and in the Universe, Cosmology and Astronomy
Sal introduces Carbon 14 in this chemistry video and explains to students how it is found in all living things. He also explains how carbon-14 is used to date items from the past. He points out that Carbon 14 can only enter a living...
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Gibbs Free Energy Example, Thermodynamics, Chemistry
Sal continues his discussion of spontaneous reactions by setting up a reaction between two substances and using the Gibbs Free Energy method to determine its spontaneity. This video is challenging in terms of math, and it would be...
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PV-Diagrams and Expansion Work, Thermodynamics, Physics
In this chemistry video, Sal explains why work from expansion in an energy transfer occupies the space underneath the curved line of a PV Diagram. Pressure is plotted on the left axis, and volume is represented on the horizontal axis of...
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Efficiency of a Carnot Engine, Thermodynamics, Physics
In the world of chemistry, efficiency is defined as: the work a system does, divided by the energy given to that system to complete the work. Sal illustrates this important chemistry concept by drawing a PV graph that shows a Carnot...
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More on Entropy, Thermodynamics, Physics
Entropy is the focus of this chemistry video. More specifically, Sal drives home the point that entropy is a macroscopic state variable. This means that a change in the universe's entropy must always be positive, because when heat is...
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Change of State Example, States of Matter and Intermolecular Forces, Chemistry
A problem from a chemistry textbook is posed on the screen. In this problem, ethanol is used to illustrate the amount of energy, in joules, required to change a substance from a liquid to a gas. The boiling point of ethanol is given, and...
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Introduction to Oxidation States
Oxidation states in elements are the focus of this chemistry video. Sal illustrates how when an element loses electrons, it is moving toward a state of oxidation, and when an element gains electrons, it is moving toward a state of...
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Work Done by Isothermic Process, Thermodynamics, Physics
Since the temperature of a system is crucial in its energy transformation, Sal examines two processes that greatly affect temperature in a system: the Isothermal Process and the Adiabatic Process. He sets up an example and illustrates...
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Quasistatic and Reversible Processes, Thermodynamics, Physics
The theories behind Quasistatic and Reversible Processes are offered in this chemistry video. Sal sets up a hypothetical situation in which gases are escaping from a piston in a car's engine. He uses this scenario to illustrate precisely...
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Thermodynamic Entropy Definition Clarification, Physics
In the previous video, Sal introduced students to entropy and the 2nd Law of Thermodynamics. An example he used had a couple of points that were factual, but not clear to many students. In this video, he goes over those points again in...
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Mini-Video on Ion Size, Periodic Table, Chemistry
Sal discusses what happens to elements when they become ionized. He demonstrates that when neutral atoms become ionized, they can significantly change their relative atomic sizes. He uses the Periodic Table of the Elements to illustrate...
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Work from Expansion, Thermodynamics, Physics
Sal's series on the Law of Thermodynamics continues with this video on how heat and work are added to, or taken away from, a system. As a result of the heat and work energy, the system that is being worked on will transform into another...
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States of Matter Follow-Up, States of Matter and Intermolecular Forces, Chemistry
Sal continues his explanation of the states of matter by focusing on hydrogen bonds. This time, he uses plasma as the substance being studied, and explains how the hydrogen bonds change as the substance goes from solid to liquid to gas.
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More on Oxidation States
In the previous video, Sal presented how elements move toward a state of oxidation (by losing electrons), and a state of reduction (by gaining electrons). This lecture takes that concept a bit further, and he provides more examples.
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Enthalpy, Thermodynamics, Chemistry
Sal introduces students to the term "enthalpy" in this chemistry video. He defines enthalpy as: the internal energy, plus the pressure times the volume found in a system. He constructs a PV diagram to illustrate this point.
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More Exponential Decay Examples, Nuclear Chemistry, Chemistry
This video is an extension of the previous video, which introduced exponential decay and showed students how to solve for it. More examples are given to give students further practice.
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Hydrogen Peroxide Correction
This very short video is used to correct an error that Sal made in the previous video regarding the solution, Hydrogen Peroxide.
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Bailout 5: Paying off the Debt
Chronicling the "first wave" of the financial crisis with a short review, Sal goes on to explain how bad choices and unfortunate moves by several banks can lead to total disruption of the financial system. Sprinkling real-world examples...
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Bailout 12: Lone Star Transaction
Departing from his trademark theoretical balance sheets, Sal guides the viewer through a real-life "outlandish" transaction between Merrill Lynch and Lone Star Funds. Budding economists can exercise their growing economic skills by...