Edit Okay, let's begin Compound, a substance composed Of two or more elements Chemically combined In definite proportions by weight Mixtures, 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 6 Left channel, right channel Hydrogen, H plus one Sodium, Na plus one Magnesium, Mg plus two Aluminum, Al plus three Pota**ium, K plus one Calcium, Ca plus two Chromium, Cr plus two, 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 You're about to play a soul, 45 rpm recording But the turntable is set at 33 and 1/3 And the record plays very slowly Let's pick up the tempo a bit, eh? Now, let us imagine That you are in the middle Of your disk jockey program This is the mark of a professional Yeah, if you could throw a couple yeah, uuh Right, when he's playin' the drum, you know Let him play a couple beats alone, euh Uh, oh, I'm sorry I had the turntable at the wrong speed Aah, listen to this, scratchin', the greatest thing on earth What do you do? What do you do? Toggle, wow, drop Chemical change, a change that alters The composition of the molecules of a substance New substances with new properties are produced Drop From now until your next lesson We want you to study carefully every section Of lesson 6 and to go back over lesson 4 Practice carefully, and you will be ready For the new techniques and new situations We will cover together in lesson 5