Determining Reaction Rate From Graph
The first of the three types of reaction rate problems most teachers make you do. In this video, we'll see how taking the slope of a graph gives you the reaction rate, and how this slope changes with time.
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Factors Affecting Reaction Rate
This video covers the reaction rate concepts and principles you'll need to know for multiple-guess, essay questions and lab reports. We'll cover the four factors that influence reaction rate, and I'll explain in "normal people language" why it makes sense that these factors would affect rate. (hint: it's all about the collisions)
This chapter covers everything about reaction rates. An introductory video covers the factors you'll need to know for multiple choice and essay questions, then three more videos explain the three ways you'll need to be able to calculate reaction rate: graphs, stoichiometry, and rate laws.
Intro to ICE Equlibrium Tables
ICE table problems (Initial, Change, Equilibrium tables) come in two major types. In the first, they give you the equilibrium concentration of one of the compounds in a reaction, and you use the ICE table to find the concentrations of everything else. The other (much harder) type of problem is when they just give you the equilibrium constant, and that's when you end up with a quadratic equation and you have to do some fancy algebra.
Solubility Product -- Ksp
Remember a couple of chapters ago when we were talking about solubility rules, and we said that some stuff is "insoluble"? Yeah, that wasn't quite the full story. It turns out that even if something isn't a big fan of getting dissolved, that doesn't mean that the water won't be able to dissolve away a few atoms here and there. Using ICE tables and the solubility product (Ksp), we can figure out the molarity of the solution!
ICE tables (initial, change, equilibrium) allow us to use a bit of algebra to determine the concentrations at equilibrium when we aren't given the equilibrium constant. Solubility products allow us to calculate the solubility of compounds which would have been considered "insoluble" in the solubility rules chapter.
Reaction Quotient
The formula for reaction quotients, Q, is surprisingly similar to equilibrium constants. The difference is that the reaction may or may not be at equilibrium when you plug the numbers in. Is it or is it not at equilibrium? That is (often) the question.
Basic Equilibrium Constant Calculations
In this video we'll look at word problems and plug numbers into the equilibrium laws we created in the last video. We'll also learn how to manipulate equilibrium constants. For example if they give you Kc for a reaction but want you to find Kc for the reverse reaction, or for double the coefficients.
Equilibrium Laws
In this video we'll learn how to translate a chemical equation into an equilibrium law (a.k.a. equilibrium constant) with the right fraction and exponents. We'll also see what to do about a few common exceptions you need to know, like if liquid water is one of the products or reactants, or if there is a solid on one side of the equation.
This chapter introduces equilibrium laws, then shows you how to plug in numbers, calculate equilibrium constants, and use quotients to figure out if a system is at equilibrium.
Le Chatelier's Principle -- Temperature
Like the other Chatalier videos, except this time we're dealing with -- you guessed it -- Temperature! Basically, this video tells you how to use the enthalpy of a reaction to deduce changes in equilibrium concentrations vis-a-vis baseline when the temperature of the system is increased or decreased. Basically.
Le Chatelier's Principle -- Pressure
This video covers problems just like the previous Chatalier Principle, except that this time rather than changing the concentration of one of the compounds, the disturbance will be increasing or decreasing the pressure of the chamber in which the reaction is taking place. Warning: applies to gases only!
Le Chatelier's Principle -- Concentration
The wording of this principle -- something about systems in equilibrium moving to reduce disturbances -- can be very confusing. But it turns out the questions for this principle are pretty straightforward (and always the same), so by the end of this video you should be able to say with certainty which direction the equilibrium is "pushed" when you raise or lower the concentration of a particular reactant or product.
What the heck is equilibrium?
This video explains the concept of equilibrium using a couple of examples everyone should be familiar with: dissolving sugar in water, and water evaporating out of a cup. Also covered: why is it called "dynamic" equilibrium? Pay attention, this is going to be a short-answer question on your quiz!
This chapter introduces equilibrium and explains how it applies to a couple common situations everyone is familiar with: dissolving sugar in water, and water evaporating to its vapor pressure in a closed container. The rest of the videos explain common questions involving Le Chatalier's Principle with respect to concentration, pressure and temperature.
Coffee Cup & Bomb Calorimeter Problems
That's not a typo, crazily enough. In this chapter there really is something called coffee cup calorimetry, so named because you could do it using an old-school foam coffee cup. Back in the day when they were styrofoam, before Starbucks (or so I've heard). The trick to the bomb calorimeters is to calculate the heat capacity of the bomb itself.
Multi-Step Heating & Cooling Curve Problems
This video covers the problem you're most likely to see on your chapter test: multi-step problems where something is heated up and then has to melt or boil. As usual, staying organized is key. You don't want to mix up your specific heat with heat of fusion or vaporization.
Freezing & Boiling, Heat of Fusion & Vaporization
For most students this is the most confusing part of heating and cooling problems. It makes sense that things heat up as you put heat into them, but how is it that they suddenly plateau and stay at one temperature as they melt or boil away? And why do I care how much heat that takes? Here you go.
Specific Heat, Single-Phase Heating & Cooling Problems
This video covers problems where you calculate the heat absorbed by a liquid that is being heated up or cooled down without freezing, thawing, boiling or condensing. It also covers problems where liquids of different temperatures are mixed, or a hot object is placed in cool water and allowed to come to equilibrium.