The Lecture

Edit. OK, let's begin! Compound: A substance composed of two or more elements chemically combined in definite proportions by weight. Mixture: Two or more substances that are not chemically united, such as air. Solution: A uniform mixture of varying proportions of a solvent and a solute. For many of our students, this is the lesson you've been waiting for. Lesson... Six. Left channel. Right channel. Hydrogen, H, +1. Sodium, Na, +1. Magnesium, Mg, +2. Aluminum, Al, +3. Potassium, K, +1. Calcium, Ca, +2. Chromium, Cr, +2, three, six. Any physical difficulty with a record, or a turntable, is taken care of. Do you think that Led Zeppelin and Frank Sinatra would go together? Edit. No. Combinations of music.