"What are you reading?" K.O. asked Elie, who was sitting before the tent, early in the morning.
"Valerie's chemistry book." She sighed.
"What do you need an elementary school chemistry book for?" The old man asked puzzled. "It is an easy thing for you!"
"I wanted to know, what the twins needed to know to take the supplementary exam."
"Elemental things. What else?"
"It's not as simple as what they should know. I have read over their books, and it was interesting to me. A lot of cute little facts and questions. But I have university degree from Chemistry! I just couldn't figure out what Valerie and Conrad should know. There's no data, or definitions, or rules, or relationships. There is no factual text. I am lost. I tried to call my aunt, who is a Chemistry teacher, but she is also lost. At least I know, that she is in the jungle somewhere."
"It is just an elementary school book!" K.O. said in disbelief and shook his head. "What difficulty can an elementary school book cause us?"
"Check it yourself!" Elie said and handed the textbook to the old man.
K.O. sat down next to Elie, and began reading Valerie's book. He was reading, and constantly shaking his head in disbelief. He sighed, when he turned the last page.
"I don't understand." He stated. "I also don't understand." He shook his head. "I have the university degree in teacher's training in chemistry too, but I have never met such a bad chemistry book.
"Have you ever taught?"
"In the old times. With chalk and blackboard." K.O. shook his head. "But the chemistry hasn't changed since then!"
"I suppose, we have to reread the book. Maybe we will understand." Elie said uncertainly.
"It is more like a scientific comics, than a learning material. Very entertaining, but how could a child learn anything from such a badly written book?"
"Well, the twins didn't learn a word, if they had failed the exam." The young woman smiled to the old man.
"But somehow we just have to prepare them for the exam!" K.O. said in despair. "I thought it would be easier. During the traveling, they could learn enough to pass the supplementary exam. That was my original plan. But it seems, it won't work."
"Do you think we should ask the twins about the questions?"
"If they knew what they should have learned, they would not have failed." He sighed.
"You are right." Elie sighed too. "I have no better idea than to re-read the book and try to extract the curriculum from it."
"Good idea!" K.O. agreed, and picked up a yellow marker. "Let's start!"
"What about the caravan?"
"I still have time to go and fetch the car." He said, and put his nose into the book again. Elie picked up Conrad's copy, and they both immersed in reading.
"Elie! What are you doing?" The twins asked in unison, when they woke up.
"I am trying to figure out the question of your supplementary exam."
"It is impossible." Valerie sighed.
"I say it is futile." Conrad agreed.
"Why?" Elie asked, surprised.
She was aware, that the twins didn't like Chemistry, and the lack of their knowledge was very big, but she didn't expected them to give up easily. Neither of their nature predicted giving up.
"Nobody knows, what to know from Chemistry for sure." Valerie said.
"Nobody? Really?"
"We just had to guess, and you either was right, or wrong." Conrad nodded.
"We were wrong." Valerie shrugged. "It was just bad luck."
"Was there anybody, who knew the answers for every question?" Elie asked the kids, although she was aware, which name was coming. Elie knew, that the answer would hurt the kids' pride and soul, but she needed to know for sure.
She was right. The twins' faces darkened, and Conrad was the one, who spitted the hated name.
"The Class rep."
"So she knew the answers for all the questions in Chemistry." Elie was thinking loud.
The twins nodded.
"I won't call her to ask any questions from her!" Valerie's face was distorted by anger.
"There's no need to ask her any questions!" Elie smiled at the girl, and tousled her hair above the white bandage. "I was just curious, whether a child, who was brought up here, could manage you Chemistry class."
"She is very good from the subject. Well, she is the best in the class in Chemistry." Conrad informed the woman.
"She could." Elie nodded and smiling contentedly. "Sure."
"Why are you so happy about it?" Valerie asked in bitter voice.
"Because it is the proof, that it is enough for you, what this Island could teach you." Elie smiled.
"Really?" The twins asked in unison. There was disbelief in their voice.
"I mean, the basic knowledge, we teach for our kids, should be enough for you too."
When K.O. returned with the repaired caravan, the twins were busy drawing in the sand of the beach.
"Hey, what are you doing?" He asked the busy twins curiously.
"We are drawing a shortened periodic table!" Conrad answered.
"We are just writing the members of the main groups." Valerie waved to the old man.
"It is great!" K.O. praised them. "Why did you do this?"
"Elie told us to do!" Conrad informed him.
"Could you draw the BAt line to this table?" Elie stepped to them.
"Hey it is easy!" Valerie cheered.
"Even upwards!"Conrad nodded, as he made the line longer. "If Helium were on top of Beryllium, it would look pretty good!"
"If we look at the number of its outer hands, that is, its valence electrons, it should really be there, but because of its physical properties similar to noble gases, it belongs to the group of noble gases." K.O. nodded.
"Noble...gas… Noble, Gus..." Valerie was thinking loud, and burst out of laughter, remembering her uncle's name. The others joined her.
"Your grandfather has a sense of humor, but he had at least 20 years ago." K.O. wiped his eyes, because he was in tears of laughter.
"Okay, so the VIII.A group's name is Noble Gases." Elie said, while tried to be serious. Gus Noble and the Noble Gases… It was much more funny, than anyone could bear it without laughter.
"They had eight hands on the surface, except Helium. It has only two."
"And Helium's hands are holding each other." Conrad nodded. "That's why they are so calm."
"The others are also calm. They have eight hands on the surface and cling to them in pairs. They don't need more hands, and they don't give hands to other atoms."
"They just gurgle peacefully." Valerie noted, remembering the gurgling Radon atoms in the cave.
"Yes. They are passive, peaceful creatures. Every other atoms want to be like them."
"The VII.A group's name is Halogens. They all have seven hands, three pairs holding hands and one is alone."
"We have never met them." Conrad said.
"No, I don't think so." K.O. shook his head. "But if Valerie gets herself and takes the coolant packs off her ears, we're going to disinfect her earlobes with one of the halogens, Iodine."
"Let's look at the names of all the groups first!" Valerie refused the offer.
"It's okay!" K.O. said. "Two elements from the following team is already known, column VI. A, the Oxygen group."
"The Oxygen and Sulfur!" Conrad said. "They have six hands, two pairs and two free hands."
"Why are the two free hands not holding each other?" Valerie asked.
"Because they are too far from each other." Elie replied. "The free hands can't hold each other on the same atom, but they could with other atom's free hands. That's how the covalent bonds work."
" What's the name of the V. A group?" Conrad asked. " We have already known the Phosphorus from them. They have one pair of hands, and three free ones."
"That's the Nitrogen group. The next one is also known. The Carbon group. With four free hands, they constitute the IV. A group."
"If we proceed in the same way, then III. In the group, the elements have 3 free hands." Valerie said.
"You are right." K.O. nodded. "They are the Earth metals."
"Are they real metals?" Conrad asked.
"Yes. They are on the other side of the BAt line. So they are metals." Elie said.
"The II. A group's name is Alkaline earth metals, with two free hands, and the I. A groups is the Alkaline metals."
"We have already known Lithium and Francium from the I. A group, and Radium from the II. A group." Conrad nodded. "They have very practical signs, but the names are difficult to remember."
"You are getting used to it in no time!" Elie consoled the twins. "Make a song from them!"
"Really, we added new verses to our song a long time ago!" Valerie was thinking, but she did not have too much of a desire to write poetry.
"Moreover what we told you is the old system of the periodic table." K.O. said. "But it is very useful, when you want to apply the eight electron rules."