Girls Like Enemies (Chapter 3)

For a week, Andrea tried to teach herself everything to know about chemistry. She took notes from her textbook, read articles on the internet and only watched movies that used science. When those seven days were up, her brain was stuffed with as much knowledge as she could remember regarding chemistry. She was so ready to use it when she got to class.
For AP chemistry, Andrea wore hipster glasses without the prescription to appear smarter. She also wore her hair in a ponytail. When the class had to do another hands-on project, Andrea hoped that her brain could help attract the attention of Randall in a positive light.
"What does Step Two say?" asked Randall after turning on the burner on the counter.
Andrea picked up the laminated paper of instructions. "It says to add the sodium chloride to the hot water."
Randall reached for the box that contained various elements. He picked up a tiny spoon and scooped the element in the section of the box titled, "NaCl". He proceeded to dump the element in the water-filled beaker.
"Did you know that sodium chloride is basically salt?" asked Andrea.
"Am I wet behind the ears?" Randall asked, all snarky.
"No, you're dry."
"Good to know." Randall picked up a swizzle stick and started stirring the water. "Okay, what's next?"
"'Step Three: Add the element labeled 'Mystery One' to the water mixture.'"
"Okay." Randall cleaned the tiny spoon with a ripped up paper towel. He then scooped the element in the box under "Mystery 1" with the spoon and dumped it in the water.
"Do you think Mystery One is silver nitrate?" asked Andrea.
"Do you even know what you're saying?" Randall asked back.
"Of course. If that's silver nitrate, it would make a double-replacement reaction since it's interacting with the sodium chloride."
"You don't say."
"I do say. And the ions of the two compounds trade places to make two new compounds while they're in water."
"Tell me something I don't know, Andrea."
"Well, what don't you know?"
"Andrea, I don't have time to play games. We're supposed to do a project and this is what we shall do."
"We are doing it, Randall. I thought that it would be cool to share with you what I know about chemistry. Did you know that the primary component of marble is calcium carbonate?"
"Yes."
"Okay, that's something you do know. But what don't you know?"
"Andrea, this is work time. Can you shut up and work?"
Andrea scowled. "Fine, Isaac Newton."
Randall chuckled. "Isaac Newton? Really? He did physics, not chemistry, you idiot."
"I know you are but what am I?" She couldn't think of a good insult to say.