In the fluorescent glare of a university lab, twelve-year-old Elena watched her older brother, Mateo, panic.
“The alcohol has microscopic air trapped inside. That air is lighter than the liquid. It’s making your volume reading wrong, but worse—it’s making your mass wrong for the space you think is full.” densidad del alcohol
“Let me try,” she said.
Mateo laughed. “You’re in sixth grade.” In the fluorescent glare of a university lab,