In this video Paul Andersen explains how the dissolution of a solute in a solution can be explained as a reversible reaction. Bonds in the solid solute are broken and the ions are dissolved in a solution. The Ksp (or solubility product...

What does an atom look like? Throughout history scientists and philosophers have attempted to answer this question. As a result, they've come up with some useful models for understanding the building blocks of our universe.

In this video Paul Andersen explains how electrochemical reactions can separate the reduction and oxidation portions of a redox reactions to generate (or consume) electricity. The half reactions can be analyzed to determine the...

Scientists have found that Valentine's Day can have a negative impact on relationships and the holiday-related obligation to be lovey-dovey may have something to do with it.

Mr. Andersen gives a brief description of matter. The five states of matter are also discussed.

We hear about calories all the time: How many calories are in this cookie? How many are burned by doing 100 jumping jacks, or long-distance running, or fidgeting? But what is a calorie, really? And how many of them do we actually need?...

For the majority of recorded human history, units like the weight of a grain or the length of a hand weren't exact and varied from place to place. Now, consistent measurements are such an integral part of our daily lives that it's hard...

Paul Andersen starts by defining transpiration as evaporation off of a leaf. He then describes how a potometer can be used to measure the rate of transpiration in different environments.

In this video Paul Andersen explains how electromagnetic induction occurs when the magnetic flux of an object changes. The magnetic flux is product of the surface area perpendicular to the magnetic field and the magnetic field strength....

Mr. Andersen describes the relationship between voltage, current and resistance in an electric circuit. Ohm's Law is introduced through a circuit simulation.

Mr. Andersen defines the terms energy, work and power. He also uses a simple example to calculate both work and power.

GPS devices aren't just for keeping you from driving into a lake. They're also helping lots of scientists in unexpected ways.

So, how many different kinds of intelligence are there? And what is the G-Factor? Eugenics? Have you ever taken an IQ Test? All of these things play into the fascinating and sometimes icky history of Intelligence Testing. In...

In this video Paul Andersen shows how carbon dioxide in the atmosphere is causing a decrease in the pH of the oceans. The carbon dioxide combines with the water to create carbonic acid which dissociates into bicarbonate and carbonate...

What happened when a gambler asked for help from a mathematician? The formal study of Probability.

The classical physics that we encounter in our everyday, macroscopic world is very different from the quantum physics that governs systems on a much smaller scale (like atoms). One great example of quantum physics' weirdness can be shown...

Paul Andersen explains pH as the power of hydrogen. He explains how increases in the hydronium ion (or hydrogen ion) concentration can lower the pH and create acids. He also explains how the reverse is true. An analysis of a strong...

Mr. Andersen walks you through the cellular respiration lab.

Welcome to Crash Course Statistics! In this series we're going to take a look at the important role statistics play in our everyday lives, because statistics are everywhere! Statistics help us better understand the world and make...

In this video Paul Andersen explains how the work is a product of the external force applied to an object or system and the distance it moves. Power is a measure of the amount of work done per unit time. The work can be calculated as...

NASA's Juno is arriving at the Jupiter System! This is our opportunity to find out whether or not Jupiter has a solid core, as well as snag some cool travel pics before descending into oblivion.

In this video Paul Andersen explains how biodiversity can be measured through genetic, species, or ecosystem variety on the planet. Species diversity is increased through speciation and decrease through extinction. The mechanism for...

Paul Andersen shows you how to graph data by hand. He explains the required elements of a scatter plot with a best fit line. He shows you how to properly scale and label the axes.

How would you measure a personality? What, exactly, is the self? Well, as you've come to expect, it's not that easy to nail down an answer for those questions. Whether you're into blood, bile, earth, wind, fire, or those Buzzfeed...