3. Mr. Tom's Mild Ride

The chemistry novel continues...

1. A Mole in the Lab
2. The Nuclear Café
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The doors burst open of their own accord, as if they were bored of being closed. And although Stefanie wasn't quite sure what a briefing was, she expected to find a classroom of some sort with desks, a chalkboard, and maybe a poster with a motivational kitten.

Instead, she chanced upon a small group of children clustered around what looked like a water ride at an amusement park. A narrow canal led a series of logs on water into a predictable sort of tunnel and then to who knows where. Several children had already made their way into the logs, although the logs seemed quite allergic to moving at the moment.

Upon closer examination, the final log seemed to be stuck to a frozen slab of water beneath it, and there would be no moving forward until its ice had melted. A young man was sprawled on the edge of the platform with a blow torch, trying to melt the ice as quickly as possible.

"Now however did that happen?!" Stefanie exclaimed.

"It's in the solid state of matter," the young man said, pulling himself up from the floor and turning to look at her. "We have to make it transition into a liquid state."

The sight of his face suddenly took her a little aback. 

"You look quite like my eight-year-old brother, Tom," she said.

"I am your brother Tom," he said, "except I'm twenty-five and quite good with a blow torch."

"But that's impossible," she exclaimed. "How could you now be older than me?"

"You are inside an atom," he said. "So, I would be suspicious about that word impossible. I expect it is the time dilation."

"I've had my pupils dilated once," she responded. "They put a puff of air in them, as I recall. Not too pleasant, but not too painful either."

"Did someone say something to you about a Lorentz contraction?"

"Yes," she answered. "There was some talk of that with regard to the shrinkage."

"So there you have it," he said, as if the matter of his greater age was now obvious.

"You see there are three states of matter," he continued. "Solid, liquid, and gas."

"Yes, everyone knows that," she protested.

"Did you know that kids?" he said, turning to the children on the platform.

"No, we didn't know that," several said.

"Yes, that's very interesting," a girl named Vanessa answered.

"Thanks, Vanessa," Tom said to a girl who looked a lot like a smaller version of Tom in a whig.

"The water down there is liquid and ready to go," he proceeded to say. "It's at normal room temperature. 

"But the water here is frozen, most likely because of the liquid nitrogen I used to try to freeze my salmon. Now look at it. There's no eating that."

And sure enough, there was a salmon frozen into the ice.

"And, since you asked, this is pure water," he continued.

"I didn't ask," Stefanie said.

"That's right. There are no minerals or other impurities in this water like there would be coming out of a faucet in your kitchen sink."

"There are impurities in my water?" Stefanie responded, now somewhat alarmed.

"Oh, don't worry," he said. "They're not dangerous. If enough people get sick or die, they put regulations on such things. All it takes is a few decades of not listening to scientists."

"Aren't they trying to take flouride out of water right now," Stefanie asked.

"No, just one rather peculiar fellow," Tom answered.

"When are we going to get to go on the ride?" Vanessa finally interrupted. "My parents are expecting to meet me at the briefing ten minutes ago."

"Fine," Tom said. "I only have two learning outcomes for this ride, and I need to make sure Stefanie has them down solid," he said with a smirk. "See what I did there?"

"No, I'm not sure what you are saying," she said with a puzzled look on her face.

"Solid -- it's one of the three states of matter. Well, four if you count plasma."

She still looked at him with a little impatience.

"Solid, liquid, gas -- the three phases of matter. It's the first learning outcome of this ride."

"Yes, yes," she said. "Everyone knows that if water is cold enough, it turns to ice. At normal temperatures, it's liquid." Then she paused.

"Oh, you can boil it and it evaporates, right?"

"Exactly!" he exclaimed. "If you put more heat into its molecules, they will become a gas. You might call it 'steam.' It's the vapor that comes off a pot of boiling water."

"Can you get on with the second outcome so we can get this ride going," Vanessa interrupted.

"Ah, yes," he said. "This water here is a pure substance. It's not a mixture of water with something else. It's just water, H₂O. Have you heard of H₂O?"

"Of course," Stefanie said. "Everyone's heard of H₂O.

"Have you ever heard of H₂O, kids," Tom said, turning to the other children again.

No, we haven't heard of that." several said.

"Yes, that's very interesting," Vanessa also chimed in.

"One molecule of water has two hydrogen atoms and one oxygen atom."

"I guess I'd never really asked what the H₂O stood for," Stefanie said. "But do these children know what hydrogens and oxygens are?"

"No, we don't know nothin' about chemistry," they said one after the other.

"Except that cesium explodes when you throw it in water," Vanessa said, and with that she secretly showed Stefanie that she had a carefully wrapped lump of cesium hiding under her jacket. "I won it in a cereal box contest."

"Everything in all the world is made up of atoms!" Tom excitedly proclaimed, flinging his arms wide open with great enthusiasm. "And if you glue the atoms together, you get molecules."

"Does anyone have Legos?" Stefanie added, eager to enlighten the children.

"No, we just play video games," one boy said. "We don't play with toys any more."

"Well," Stefanie tried to continue, taken somewhat aback. "They were these little blocks you could stick together and build things. That's like the atoms and molecules of the world that Tom was talking about."

"I like Legos," Vanessa said, "although I prefer Thomas the Tank Engine."

"That sounds boring," the boy said.

"So H₂O means that water has two hydrogen atoms and one oxygen atom," Tom continued. "But the water you get from your kitchen is a mixture. It has water in it, but it also has things like iron and sometimes flouride and other substances.

"Isn't that dangerous?" another boy named Lane asked. "I mean, do they unplug the iron before they put it in the water?"

"ABSOLUTELY you must NEVER let anything plugged in near water or you might electrocute and kill yourself," Tom said in the most emphatic tone yet.

"It's not that kind of iron," Stefanie added. "There must be some atom named iron."

"An element!" Vanessa said. "The atoms are called elements, right?"

"Yes," Tom continued, trying to steer everyone back to the topic at hand. "Iron is a type of atom, an 'element,' as Vanessa said."

"And they call an iron an iron because it's made up of iron?" Lane asked.

"That's quite clever of you to suggest," Tom answered. "And they were when the iron was first invented, but that's a topic for another day. Right now you need to know the difference between a pure substance and a mixture."

"That's easy!" Vanessa protested. "A pure substance is just one thing. A mixture is more than one thing."

Tom paused, as if she had stolen his thunder.

"Yes, more or less," he finally answered.

"And a pure substance probably could either be a single element, like iron," Stefanie interjected. "Or a few atoms glued together, like water -- a molecule, right?"

"Yes," he said, bending over and whispering to Stefanie. "But I'm supposed to be the teacher in this scene."

"Are there different kinds of mixtures too?" Lane said.

"Why, yes," Tom answered. "I'm glad you asked."

"There are mixtures where everything is so evenly distributed that you can't see any differences in what you're looking at. For example, you can't tell that iron is mixed with the water in your sink."

"Or in the different elements mixed together in the air, right?" Vanessa threw in.

"Except when the light comes in the window and you can see the little particles hanging in the air," Lane added.

"Yes, yes," Tom tried to regain control of the conversation. "Those are called homogeneous mixtures --without the particles you see in the air."

"Homo what?" Stefanie asked.

"Homogeneous -- it means everything is spread throughout evenly."

"Then why didn't they call it a spread-throughout-evenly mixture?" Stefanie responded.

"Because that involves dashes and isn't confusing enough," Tom answered. "It can also be called a solution, if it's a liquid. Does that make it better?

"So what would you call this kind of mixture?" Lane picked up a stick on the platform and threw it into the water canal for the ride.

"An annoying one," Tom said. "because now I have to fish that out before we can start the ride.

"And the salmon," Stefanie said.

"But a mixture with a stick or salmon in it is called a heterogeneous mixture," he continued, "because now the materials are differently distributed in it. It's not all smooth throughout."

"So let me summarize so we can get this ride going," Vanessa said. "There are pure substances and mixtures. Of the pure substances, there are individual elements like iron, but there can also be single molecules like water, pure water."

"Yes," keep going, Tom said.

"Then with mixtures you can have solutions that are evenly distributed throughout, called homogeneous mixtures. But you can also have mixtures that aren't evenly distributed throughout, called heterogenous mixtures."

"Superb, Vanessa," Tom added. "I think you have it! And look, the blow torch seems to have completely melted the ice and brought it into a liquid state."

He had carefully suspended the torch over the water to keep heating it while he talked to Stefanie and the children.

"But isn't there another learning outcome you haven't covered?" Vanessa asked.

"And what would that be?"

"The difference between a physical property and a chemical property," she said.

"Ah, yes, we might be able to slip that one in as well before we get on the ride," Tom responded. "A physical property is like the difference between water as a solid, a liquid, or a gas. It's changing its state, but it's not really interacting with anything.

"Then a chemical property would have to do with how something might interact with something else," he continued.

"Like cesium," Vanessa added. "Water would have a chemical reaction with cesium."

"Yes, certainly," Tom answered. "The water would have quite a dangerous reaction with cesium," he said, "and that would have to do with the chemical properties of cesium and water."

"Like this," Vanessa said, pulling out the wrapped up cesium under her jacket and throwing it into the water canal. The result was quite a massive explosion that abruptly brought this chapter to an end.