“Okay,” he taps the page. “This is what they want. Strong acids dissociate more completely in water. Weak acids don’t. That difference changes pH, and that changes how fast reactions happen.”
Elise squints at the numbers. “Why do I have to learn chemistry again? This stuff makes me feel stupid.”
“It’s not you,” Seth drags the book closer and flips the pencil between his fingers. “It’s the way they explain it. Look.”
He writes a few steps out, slower than he normally does anything, and slides the paper toward her. His pen taps the equation again.
“This part is the whole problem. If you understand what’s dissociating and what isn’t, the rest is just math.”
Ryan leans in. “So HCl is strong, right?”
Seth nods. “Yeah. Hydrochloric acid is strong. It breaks apart easily in water.”
Elise points at another line. “And this one?”
“Acetic acid is weak,” Seth circles part of the equation as he speaks. “It still reacts, but not the same way. That’s why the pH changes differently.”
He pauses and looks up at both of them, like he’s deciding how to translate this into something they’ll remember.
“If you mix the wrong stuff, somebody passes out.” His eyes drop back to the worksheet. “If you mix other wrong stuff, somebody won't wake up.”
Elise’s eyes narrow. “That’s not helpful.”
A faint smirk pulls at Seth's mouth. “It is helpful. It just depends on the situation.”
Ryan lifts his head. “Is that going to be on the test?”
Seth’s mouth twitches. “It should be.”
I shoot Seth a look over my wine glass.
He glances at me like he can feel it. “What?”
“You know what,” I narrow my eyes at him.
He points his pen at the book again. “I’m teaching them chemistry.”
“You’re teaching them crime,” I mutter.
Elise snorts before she can stop herself. Then she covers it with a cough like she’s embarrassed she laughed.
Seth finally looks amused. “Acids deteriorate flesh,” he flips his pen, still looking at the page. “That’s chemistry. Not crime.”
I lower my glass slowly. “Seth.”
He turns his head just enough to meet my eyes. “What? It’s true.”
Ryan makes a noise that might be a laugh. “That is so gross.”
“It’s accurate,” Seth shrugs and taps the worksheet again. “Accuracy gets you points.”
Elise stares at the worksheet again. “I hate this.”
“No, you don’t,” Seth replies. “You just don’t understand it yet.”
Ryan points at a problem. “So is this one a strong acid or a weak acid?”
Seth leans closer and starts explaining. Elise finally solves the problem and shoves the paper toward Seth like she’s challenging him to tell her she’s wrong.
