The Story of Chemistry
In 1869, Russian scientist Dmitri Mendeleev assembled a table of chemical elements that revealed an extraordinary, unifying order of all detectable matter in the universe.
He didn’t just guess. What did he know? What experiments provided the key information?
These are the questions that drive the laboratory explorations in this course. Students follow a 200-year journey of discovery, beginning in the 1600s, before chemistry was even a cohesive discipline of study. Early scientists began building theories on the nature of fire. From here, students steer directly into the chemical and physical properties of atoms and begin to chart a course mapping out the patterns under which atoms react and combine.
Five Lab Series
1. The Chemistry of Fire and Gas
What is the chemistry of fire?
Fire and animals share a curious set of similarities, which mystified and captivated a group of 18th century chemists. Both fire and animals are warmer than the surrounding air and both fire and animals consume gas and emit gas. Students run experiments and try to uncover the basis for these similarities. From here, there is a direct path to making sense of the most elusive state of matter - gas, a new theory of fire, and a solid foundation for a new science.
2. The Chemistry of Atoms
How can you prove atoms exist?
Today, we know atoms literally make up everything. And we know these atoms combine in countless ways and that this process can be beautiful, surprising, and explosive. This was not always the case. The debate of the existence of atoms raged for over a century spilling into the early 1900s.
The issue was that you can’t see atoms! You can’t just claim something exists without evidence. Early chemists had an idea, though, to make their case. If atoms were a thing, they reasoned, there is one thing they all must have. And that is mass, which is easily measured. To this end, students run lab after lab, tracking the mass change in chemical reactions, to hopefully not only build a case for atoms, but actually know what they do inside every chemical reaction.
3. Elements and Reactivity
Where are the elements—and what happens when they combine?
Where are these things, which we now call elements? Where is gold? Where is hydrogen? Where is sodium? Where is californium? In the forest? Have you ever seen a pile of lead or bismuth, just laying on the ground? Where is this stuff? In this lab series, we find them and then probe their chemical properties looking for trends lurking amongst the chemical elements. A big question emerges, however, on the relationship between elements and compounds. How can compounds be so different from the elements that make them up?
4. The Chemistry of Air and Water
What is the mass of an atom?
What distinguishes one element from another? Many elements are the same color, many are metallic, many are reactive, many are non-reactive. So what is it that makes oxygen, oxygen and gold, gold? The hypothesis students grapple with is that the one property which is not shared by any two elements is atomic mass. Proving this is not easy. Atoms are small and therefore can’t just be placed on a scale!
Students are challenged to combine the results from several different experiments and discover a way to cleverly deduce the mass of elements. Students see the easiest window into this world is the elemental gases. Out of these investigations, not only does a definitive idea of atomic mass (well, relative atomic mass) emerge, but the exact nature of the elemental gases becomes clear.
5. The Formula of Chemistry
How do you uncover the formula of a substance?
Now that we know the mass of the gases, it should be a simple matter to repeat the process and find the mass of every other element, right? Not so fast. Nature doesn’t reveal its cards that easily! It takes looking at the interesting and varied ways elements combine in chemical reactions to figure the mass of each participating in the reaction. But once this is known, the mass of every single element can be found. And once this is known, the chemical formula of everything can be found!