in sodium chloride, each chloride ion is surrounded by, and holds, six sodium ions. each sodium ion is surrounded by, and holds, six chloride ions. this results in a rigid, ordered pattern of alternating positive and negative ions. nacl is the formula of sodium chloride. it implies there is one ion of sodium for each chloride ion. that one-to-one ratio of the ions exists throughout the cubic crystal. dr. jeffrey post, a crystallographer for the smithsonian institution, studies mineral crystals, like salt. if you took a magnifying glass and looked at the salt crystals from your saltshaker at home, you'd see that each of those crystals looks like this crystal on a smaller scale. under an electron microscope, magnified hundreds of thousands of times, the crystal shapes are exactly the same, the same cubic shape. that's an inherent property of he structure. the lattice structure formed by the ions give sodium chloride and other salts distinct properties unique to ionic compounds. i have two crucibles. both contain white, crystalline solids. they look much the same. howev

chloride which, because of its chemical properties, is even more corrosive than the traditional sodium chloride rock salt. he runs a repair shop in greenbelt and he's busy fixing tires flattened by potholes today but he knows his customers' cars are suffering from that ugly white coating as well. >> just basically rust out the whole subframe of the vehicle. it causes parts like brakes rotors, things to deteriorate, ball joints. rough on a vehicle. >> his advice get to a car wash that sprayed the underside of your vehicle like this one in lanham. the manager randy evans looks forward to the days when the salt and brine go down. >> oh, yeah, i have no problem with that. definitely. great for car wash and great for the business. >> when you get to a car wash like the touchless here, you want to make sure you're not just concentrating on the paint, on the top side of the car. you really have to get down here and get underneath. that's where all the damage is done. a good rainy day will take care of a lot of this as well. but we don't seem to have any of those in the forecast. you might want to brav

. >> sodium pentothal renders the prisoner unconscious. pabalon paralyzes the muscles. potassium chloride the heart. >> there are times when i wanted them to execute me. maybe because the weight of dealing with the issue, it gets unbearable. i mean, you wanted to say, man, look, i quit. i'm going to drop my appeals. >> i don't think there is any good way to have to take a life. the side bar to that, of course, is that the individual who's being put to death took a life. i look at it as just the general public or the state of alabama actually carrying out the execution. i just happen to be the tool in place to be able to do it. if i refuse to do that, then i'm actually refusing to carry out a law that i said i would uphold. >> i started it. i'm responsible for all four deaths because if i'd have never started the killing, none of it ever would have happened. in some way, i wish that there was something i could do to help the victims' families find closure or make peace with what happened. i can't do anything but apologize. >> in 2005, the u.s. supreme court ruled it unconstitutional to imp