Watch Faraday's Lecture 1, Sources of the Flame
Read or Watch
• Atoms, at How Scientists Know
• Fun with the Elements
Matter is made of atoms, which can join with each other to form molecules.
Substances containing only one type of atom are called elements. Example: helium (He). Substances containing two or more types of atoms are called compounds. Example: sodium chloride (NaCl).
There are about 120 different types of atoms, each represented on a chart called the Periodic Table of the Elements, like this one:
Click anywhere on this table to visit a larger version at the journal Science. Hover over any square in that table to see the name of the element and a haiku about it. See how many if the haiku you can explain from your own knowledge of that substance. If it's not many, fear not. In our course, many of them will become familiar (with no memory work!). Or go to Wikipedia and look up an element with a puzzling haiku, and see if a little reading will let you in on the secret. Many thanks to Mary Soon Lee for this fascinating and educational version of the periodic table, which she calls Elemental Haiku. For more about Mary Soon Lee and her other works, click HERE.
• States or Phases of Matter
Chemists deal with and think about matter in three phases: solid, liquid, and gas. All particles of matter, in all phases, are in motion at any temperatures we encounter, because of their inherent heat content. Another way to put it is that all particles are in motion at any temperature above absolute zero, the lowest possible temperature, which is called 0° K (Kelvin, or absolute), and is equal to -273.15 C (Celsius) or -459.67 F (Fahrenheit).
In a solid, the atoms or molecules (let's call them particles) are bound tightly together, and so a solid holds its shape, without the need for a container. Despite the binding, the particles vibrate because of their heat content. Think of a room crowded with people, all tied to their nearest neighbors, so that each one can move only slightly out of position. The solid state of water is called ice, or H2O (s). It is the most common state of water at temperatures below 32 F (0 C).
In a liquid, the atoms or molecules are in contact with each other, but not rigidly bound, so they slide past each other and jostle each other. Think of a room crowded with people, but all able to move through the crowd. The particles of a liquid in a container move to the bottom of the container and take the shape of the occupied part of the container. The liquid state of water is called water (of all things), or H2O (l). It is the most common state of water at temperatures between 32 F and 212 F (0 C and 100 C).
In a gas, the atoms or molecules are far from each other, and they are in rapid motion, which is sustained by the heat of the container and its surroundings. A closed container of gas is mostly empty space.
See a program that simulates the behavior and properties of gases HERE.
In an open container, a gas will escape into the open air. Think of a people emerging from a concert hall and dispersing into the night in all directions. The gaseous state of water is called steam, or H2O (g). It the the most common state of water at temperatures above 212 F (100 C).
• Chemical Equations
Following are equations for two processes described or suggested in Lecture 1:
• Melting and vaporization of wax
• Read this poem
Telescope, Louise Glück
Submit Your questions using the instructions at the bottom of this page.
Your questions help me to keep the course at your level.
Additional Resources (optional)
• What are MOLECULES, and how do we know about them?
Commentary on Lecture 1
by the producers of the video series
••••••
Quick Look: Capillary action in Thin Layer Chromatography
Chromatography is a method of separating a mixture of substances into their pure components. The clear liquid is rising up the white surface, carrying the pigments in the spot (first image, a spot of an extract from spinach leaves) at different rates, thus separating them for further study.
