On a recent Thursday morning, Room 712 was abuzz with activity as Class 5 students collaborated to craft their own chemical lab procedure. “Be as detailed as possible when writing your procedures so anyone can replicate your experiment,” advised Class 5 science teacher Anna Mello. “Plan with your partner to determine how you’ll do the reaction and collect data.”
The energetic students were creating their own investigation to determine whether mass would be conserved during a chemical reaction. In this case, between copper sulfate and sodium hydroxide. Prior to the lab, the students reviewed the differences between open and closed reaction systems, the latter of which would be their focus for their experiment.
In the back corner of the room, numerous tools were available including flasks, test tubes, stirring rods, graduated cylinders, beakers and stoppers. “Why is the stopper so important?” prompted Ms. Mello.
Students piped up, “It makes it a closed reaction system!”
The goal, Ms. Mello explained, was to determine if the mass of reactants will equal the mass of the products. “We practiced a lot,” she said, noting that her students were very excited for the culmination of creating their own procedures.
As the students wrote feverishly, Ms. Mello circled the room to double check that students were indeed documenting all of the proper instructions. “Remember to include units of measurement,” she instructed one group. “Remember,” she added, addressing the whole class, “You all have one constraint: Don’t go above 20 milliliters.”
Once their procedures were in place, the students created a data table, into which they would insert the qualitative and quantitative information collected.
Finally, they were ready to begin their experiments, but first, the scientists ensured their safety by securing a protective smock over their clothes, tying back long hair, and donning gloves and goggles.
After gathering their chosen materials and clearing their lab tables of any personal items, the students began to gently mix vibrant blue liquid (copper sulfate) with a water lookalike (sodium hydroxide) inside their selected vessel. The result? A cobalt blue solid!
Several reactions echoed across the room as the students observed the results. “Wow! Look at the color,” exclaimed one pair. “The beaker feels warm,” said another. A third, taking a gentle sniff said, “Smells a little weird.” This unique reaction, called a precipitate, occurs when a solid is formed from a liquid solution.
As the period neared its end, the students vigorously washed their hands and sanitized their lab tables, ready to analyze their findings during the next day’s Chemistry lesson.