Chemistry: Fun with Matter

Chemists in the class Chemistry: Fun with Matter today learned about the importance of quantitative data.

“It’s more important to scientists than the more descriptive, narrative qualitative data,” Teacher Brian Marquardt said.

But, getting that data proved difficult for students who were trying an experiment for the second and third times today.

“This is our third time doing it,” admitted Giulia. “The first time we waited too long to add the iodine so it didn’t react.”

“The second time we forgot to add the starch,” Lynnea added.

Giulia was proud to say that attempt number three seemed to work. “This time we did it right.”

According to the lab instructions, the experiment involves biological catalysts – enzymes – and discovering what it is that influences the activation of a particular digestive enzyme, amylase.

The experiment was an effort to “learn what amylase does to starch,” Giulia explained. “It (amylase) breaks apart starch into sugar, from a long chain of glucose into single molecules of sugar.”

Or, in lay-person’s terms: “We’re learning about enzymes in the body and how you dissolve things you eat,” Giulia said.

Light readings are used to determine how much the starch has broken down. The chemists shine a beam of light through the mini beakers and a detector measures how much light shines through. The darkness of the liquid indicates the amount of starch remaining; the darker the liquid, the more the starch.

At another lab table, Abby and her team were using the light test. “We put different amounts of amylase each time we do the test to see how much the light shines through.”

“We figure out how much light gets through the liquid and how much is absorbed,” Olivia said.

Olivia, Mia, and Abby had run the experiment two times and were processing the data they accumulated.

“We don’t know the result yet because we don’t have all the data,” said Olivia. “We have to do more experimentation.”

They suspect a mistake was made in the first attempt. “We believe we messed up the order of when we dropped in the iodine,” Olivia said.

“We’re supposed to put iodine in every 15 seconds, but we did it every 10 seconds,” said Abby.

The good news is that the scientists learned not only from their successful experiments, but also from the not-so-successful ones.

“We learned you have to work quickly and to read the directions,” Lynnea concluded.