Visual observations were recorded. 4.4 Identification of Macromolecules in Household Substances

Nine test tubes were labeled in sets of three: "B1," "B2," "B3"; "S1," "S2," "S3"; and "L1," "L2," "L3." Two ml of baby formula solution was added to ach of the "B" tubes, tow ml of sports drink solution to each of the "S" tubes, and two ml of lemon-lime soda solution to each of the "L" tubes. The procedures used for the positive tubes (those labeled with a "+") in the experiment above, section 4.3, were then applied to these tubes -- tubes "B1" "S1" and "L1" all received two ml of Benedict's reagent, were heated at 100 degrees Celsius for three minutes and placed in test tube racks; tubes "B2" "S2" and "L2" all received a dropper full of iodine and were gently shaken before being placed in the test tube rack; and tubes "B3" "S3" and "L3" all received two ml of Biuret reagent...

Observation was again made with the naked eye and recorded.
4.5 Addressing Unexpected Results

Four pairs of test tubes were labeled "FR"/"FP," "GR"/"GP," "SR"/"SP," and "CR"/"CP." Two ml of fructose were added to each of the first pair tubes, two ml of glucose to each of the second pair, two ml of sucrose to the third pair, and two ml of citirc acid to the final pair. Two ml of Benedict's reagent were added to tubes "FR," "GR," "SR," and "CR"; these tubes were then immersed for three minutes in a beaker of water atop a hotplate heated to 100 degrees Celsius. Two ml of Biuret reagent were added to tubes "FP," "GP," "SP," and "CP"; these tubes were then incubated at room temperature for ten minutes, and results were again observed with the naked eye and then recorded.