Osmotic Pressure
Osmotic pressure is the pressure across a semi-permeable membrane arising from a difference in tonicity (hypertonicity or hypotonicity) on the two sides of the membrane. What the heck does any of that mean? Tune in to find out.
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Osmotic pressure caused by semi-permeable membranes: what is it, why does it happen, and how to do osmosis calculations with ideal gas law.
Freezing point depression, boiling point elevation. That's about it.
Boiling Point Elevation
This is the other colligative property that most chemistry classes cover, where you use the molality of a solution to figure out what it's freezing point is. Unlike freezing point, the boiling point actually goes higher. Go figure. This video has lots of examples, including calculating the molar mass using boiling point. And don't forget i!
Freezing Point Depression
The first of the two colligative properties that most chemistry classes cover, you can use the molality of a solution to figure out what it's freezing point is. Hint: it's always lower than the pure solvent. We can also use freezing point to determine molar mass, which you may very well do in a lab this chapter, so look sharp. And don't forget i!
"i" & "m"-- The X-Factors In Colligative Properties
"m" actually isn't that bad -- it just stands for molality, which isn't so bad as long as you don't confuse it with molarity. "i" however is a different can of worms, and very easy to forget in those boiling point elevation and freezing point depression problems.
Net Ionic Equations Special Situations
In the last video we covered everything you'll need to know for most net ionic equatio problems. But there are a couple exceptions you have to look out for -- acids/bases and carbonate, mostly -- which can catch you unawares if you don't catch them first.
Net Ionic Equations
These problems seem pretty crazy and algebra-ish when you first see them: ions going every which way, stuff getting canceled from both sides of the equation. I ain't gonna lie, these can get crazy. But as long as you follow these same simple steps each and every time, they start not seeming so bad.
Solubility Rules
Your teacher either has you using a "chart" or "rules" to determine the solubility of ionic compounds (in other words, how to find whether it is aqueous or a precipitate), but either way, you're probably still confused by what the heck this means. So we'll go through both methods and work some examples, and as usual I'll implore you to find out from your teacher how it will be covered on the test.
This chapter explains how to use solubility charts to determine if ionic solids are soluble or insoluble, whether they precipitate, and how to write net ionic equations.
This chapter covers the definition of electrolytes, how they dissolve or dissociate in water, and what the heck "strong" and "weak" mean when dealing with acids and bases.
Strong vs Weak Electrolytes, Acids & Bases
Unfortunately, strong and weak mean something totally different in chemistry than the do in regular life. Strong tea, for example, is concentrated tea. In chemistry, that would be "high molarity" tea. "Strong" -- when referring to acids and bases -- actually means something quite different, as explained in this vid.
Dissolving vs Dissociation
Everything that dissociates dissolves, but not everything that dissolves dissociates. This video will show you how to tell the difference, and put you one step closer to getting that multiple choice or essay question right on your next test.
What Are Electrolytes
This video explains what electrolytes are, how to spot them, and how they conduct electricity.
Dilution Problems
This video covers a particular type of problem that every teacher asks. There are two versions. One asks you to calculate the concentration of a solution created by diluting an existing solution with water, usually using the equation M1V1=M2V2. The other asks you the concentration of a solution formed by combining two solutions of different concentrations.
Mass Percentage, ppm, Mole Fraction, etc
This video covers all the obscure units of concentration that you'll see on the test in this chapter, but then never see again until the final or AP exam.
Molarity vs Molality
These are the two most common units for concentration, and unfortunately they're also the most confusing since they're exactly the same word except for one letter. This video explains how to calculate both, how to spot the difference, how they are handled differently in the lab, and the types of questions your teacher is likely to put on the test.
Also covered: parts per million (ppm), parts per billion (ppb), mass ratio (wt/wt), mole ratio (X), mass percent, and those dilution problems where you have to calculate the concentration of a solution after it's been combined with another.
Ionization Energy Calculations Using Rydberg Equation
One of the many uses of the Rydberg equation (oh what a wonderful equation!) is calculating the ionization energy of a hydrogen atom. What fun! What splendor! Quick man, to the calculators!
Ionization Energy & Electron Affinity on Periodic Table
Sort of like what happened with electronegativity, the periodic table won't give you a number for ionization energy of each element. But almost all chemistry teachers require you to know the general trends of ionization energy, and you'll need to be able to compare two atoms and say which one has a higher first and second ionization energy.