It was another science experience in Mrs. Griffin’s class, as students made predictions and journaled about their observations. Mrs. Griffin submerged 4 eggs in clear plastic cups filled with vinegar, and together, the class made predictions of what would happen. Students thought the eggs might crack, change color, dissolve, break open, float, melt, stay the same, and become transparent. As Doc the scientist told the kids, “You set up your egg experiment, and now what do you have to do? Wait! It takes a lot of patience to wait for the experiment to occur.”
After four days in the vinegar, the students observed that the water was yellow, there were dried up bubbles and the eggs cracked, among other things. Mrs. Griffin put two eggs on the smartboard, showing that the one that had been soaked in vinegar had gotten bigger and the color changed. When asked about the white “stuff” around the rim of the cup, students thought it might be the shell. Mrs. Griffin asked them to touch it and them rub their fingers together. Asking what it felt like, Abigail responded, “I think it is the shell because it feels hard and feels like the shell.” Some of the eggs popped and others remained intact. When touching the intact eggs, the shell felt soft.
After observing and touching the eggs, Mrs. Griffin asked the students to remember their predictions, and some of them actually happened. Mrs. Griffin then asked the students what they thought happened to the egg shell? After a couple of thoughts from the students, she exclaimed that when the calcium carbonate, which makes the shell of the egg hard, combined with the acid of the vinegar, a chemical reaction took place. A gas called carbon dioxide was released, causing the bubbles, and once of the carbon dioxide was completely released from the egg, the shell became soft.
Following several more questions and student responses, students washed their hands and moved onto the next topic…fractions!