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Oxidative Phosphorylation and Chemiosmosis
Salman Khan reinforces the balancing of the equation through the electron transport chain and then elaborates on relevant vocabulary.
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Electron Transport Chain
The third video in the respiration cycle sequence provides an excellent lesson on the electron transport chain.
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Inflammatory Response, Human Anatomy and Physiology, Health and Medicine
Sal describes the cellular activity that occurs when there is damage to our membranes.
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CAM Plants
This lecture continues the concept of CO2 being stored in the form of acid before it is used in photosynthesis.
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Ape Clarification
A short video to clarify that the sketch in a previous video was incorrect. Apes DO NOT have tails.
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Chilling Water Problem, States of Matter and Intermolecular Forces, Chemistry
Sal continues this short series on specific heat and vaporization. The situation he poses uses 500 grams of liquid water at 60 degrees Celsius to get the water to zero degrees Celsius. The ice he adds to the water comes out at -10...
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Vapor Pressure, States of Matter and Intermolecular Forces, Chemistry
Vapor pressure is the focus of this chemistry video. Sal explains that when molecules are "sticking together," a substance takes on a liquid or solid form. However, when kinetic energy increases, the molecules are forced apart, allowing...
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The Mole and Avogadro's Number, Atomic Structure and Properties, AP Chemistry
Sal introduces chemistry students to the concept of "moles." He points out that a mole is a unit of measurement that helps a student to convert between grams and atomic mass units of any substance. Sal uses the element Aluminum to...
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Entropy Intuition, Thermodynamics, Physics
Sal provides two definitions for entropy: the thermodynamic definition and the mathematical definition. Entropy and the 2nd Law of Thermodynamics are the focus of this chemistry video. The law states that the change in entropy in the...
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States of Matter, States of Matter and Intermolecular Forces, Chemistry
The three states of matter are the focus of this chemistry video. Sal uses the example of a water molecule and explains in great detail the forces present that allow the molecule to change between a liquid, a solid, and a gas. Of course,...
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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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Worked Example: Calculating Partial Pressures, AP Chemistry
Figuring out the partial pressures of various gases in a container is the focus of this chemistry video. Sal sets up a problem where a balloon is filled with three different types of gases: oxygen, hydrogen, and nitrogen. The goal is to...
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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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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...