Chapter 378 (1/2)

Chapter 378: Oxygen and Nitrogen

Translator: Meh/TransN Editor: – –

Agatha, Sylvie, Chavez and Kyle Sichi would conduct the experiment. Carter, Iron Axe, Barov and all the other witches of the Witch Union were also required by Roland to come to the lab, as it was an experiment of great practical and educational significance. The fifth laboratory was chosen for this event, given that it was the largest lab and had enough space for the two dozen people.

Considering the experiment was the first of its kind, Roland had built a tower-shaped vessel which was only as tall as a man with a diameter of one meter instead of a giant fractionation vessel. The inside of the vessel was divided into three parts. The air would enter the vessel through the bottom part and come out through the two parts above.

Before separating the air, Roland gave them a simple lecture on chemistry, telling them what was going to happen and putting forward a few questions for them to think about and try to answer. It was a trick frequently used by chemistry teachers to intrigue their students and enhance the effects of the lesson.

“… theoretically, when Agatha cools down the vessel and brings down its internal temperature, the air inside will gradually be condensed into liquid, and drip down into the bottom of the vessel through the holes in the plate. So when you see liquid at the bottom, please let us know.”

Roland explained to Sylvie in detail, because no one except her could directly see into the vessel and describe the changes happening inside.

Sylvie nodded somewhat skeptically, “Will I really see liquid appear? Will it not be only the water vapor inside the vessel?”

“No, it’s different. The liquefied air is light blue, completely different from water vapor.” Roland shook his head and explained further, “Plus, at that temperature, the water vapor will be solidified into ice crystals long before the air.” Then he made a gesture toward Agatha and said, “Let’s get started.”

“Wait… Do we not have to plug up the hole in the vessel’s bottom now?” she asked.

“Block it up later. Otherwise, the vessel won’t have enough air inside to bring about significant changes.” As this was only an experiment, he chose the easiest way for air intake—when the air temperature inside the vessel was rapidly lowered, the internal pressure would fall, and thereby draw the air into the vessel. In mass production, cooling down the air cost too much energy and the cool air would run off continuously. Therefore, this cooling method was considered inefficient and rarely applied in practice. However, Agatha’s magic power could bring down the vessel’s temperature more efficiently than any refrigerators, saving Roland the trouble to prepare an air pump.

Agatha took a deep breath and pressed her hands onto the fractionation vessel.

About half a minute later, whistling sounds could be clearly heard as the air was rapidly passing through the air intake pipe. White frost could be seen by the naked eye around the pipe hole, and its area gradually expanded—the water in the air nearby was quickly solidified, and then adhered to the vessel. Anna turned her Blackfire into threads to clean up these continuously thickening ice crystals.

“I see some liquid appearing on the plate, but there’s more white frost inside.” Sylvie said in an amazement a moment later.

“The white frost may be the solidified water vapor or the crystallized carbon dioxide,” explained Roland. “Considering that there’s only a small portion of carbon dioxide in the air, most of it should be solidified water vapor.”

In normal production, air must be dried out first before being sucked into the fractionating vessel. Otherwise, the solidified water vapor would block the parting plates and the holes, and thus decrease the production efficiency.

Several minutes later, Sylvie reported to Roland that the bottom part of the vessel had been filled with light blue liquid. Roland immediately instructed Soraya to block the holes in the air intake pipe and seal them with coatings.

The next thing to do was heat the vessel, a crucial step in this experiment.

When the liquefied air was heated, the nitrogen would first reach its boiling point, vaporize and run off due to the different boiling points of nitrogen and oxygen. In this way the two could be separated. Due to the fact that Roland forgot the exact temperature at which nitrogen reached its boiling point, and that he had no way to measure it either, it all depended on Agatha to control the temperature. If she managed to heat the fractionation vessel to the right temperature, the nitrogen gas would come out via the exhaust pipe and the liquid in the bottom part would grow bluer and bluer, with an increasing purity of oxygen.