2025 Lab Chemistry

LAB Chemistry Class

"Hydrocarbon Solubility" Students in Teacher Cherise’s EP M6 Science class investigated the relationship between molecular polarity and solubility. In this hands-on lab, students compared how different substances mix with water. They set up three test tubes: one with only water (polar), one with water and ethanol (partially polar), and one with water and kerosene (a non-polar hydrocarbon). After gently shaking each mixture, they observed that water and ethanol mixed completely into one layer, while water and kerosene quickly separated into two distinct layers, with kerosene floating on top. Using the principle “like dissolves like,” students concluded that polar substances mix with other polar substances, while non-polar hydrocarbons are insoluble in water. This experiment provided a clear, visual demonstration of how intermolecular forces and molecular polarity determine whether two liquids are miscible or immiscible.

"Boyle's Law lab" Students in Teacher Cherise’s EP M5 Science class explored Boyle's Law through a hands-on experiment using a syringe and a marshmallow. Each group sealed a mini marshmallow inside a syringe barrel. By pulling the plunger out, they decreased the pressure on the trapped air, causing the marshmallow to visibly expand. When they pushed the plunger in, they increased the pressure, causing the marshmallow to shrink. By repeating this process, students directly observed the inverse relationship between gas pressure and volume. They recorded their qualitative observations in a data table and later reinforced the concept by solving quantitative calculation problems. This simple and engaging activity allowed students to verify Boyle's Law by witnessing how the volume of the air pockets inside the marshmallow changed predictably with pressure.

"Saturated and unsaturated hydrocarbons" Students in Teacher Cherise’s EP M6 Science class investigated the differences between saturated and unsaturated hydrocarbons in a practical experiment. They compared the reactions of two types of oil with potassium permanganate (KMnO₄), a purple oxidizing agent. Students added mineral oil (a saturated hydrocarbon) and vegetable oil (containing unsaturated fatty acids) to separate test tubes of KMnO₄. They observed that the mineral oil did not react, leaving the KMnO₄ solution purple, while the vegetable oil caused the purple color to fade or turn brown. This visible reaction confirmed that vegetable oil contains carbon-carbon double bonds (unsaturated), which can be oxidized by KMnO₄. This simple but effective test helped students visually identify and understand the chemical distinction between saturated and unsaturated compounds based on their reactivity with an oxidizing agent.