Jean Lab

    In this lab, we asked the question, what concentration of bleach is the best to fade the colour out of new denim material in ten minutes without visible damage? We found that 25% was the best concentration of bleach to fade denim without excessive damage. The average for colour removal and fabric damage ,for the 100% concentration, was eight for both. Meanwhile, the 25% concentration had an average of four for fabric damage and three for colour removal. The colour of the 50% concentration became light blue, but the 100% concentration became completely faded, losing its colour. Meanwhile, the 25% concentration faded enough that it was no longer dark blue. Bleach is known to break down pigments and also damages the structure of the material. This data supports our claim because it shows that when there is too high of a bleach concentration, the material will endure severe damage and lose of its colour.

     Our data contradicts the expected results because some errors came up during the experiment. Because we did not have timers, instead we relied on the clock, the period of the jeans being soaked in the solutions were not all equivalent. Another error was that because of time constraints, not all the denim rested for nine minutes. Because of this, the 100% concentration pieces did not fully reach its most faded. To improve the lab, I would have provided the groups with a timer to time the soaks perfectly. Another improvement that could have been done, would have been to have more time to carry out the experiment.

    This lab was done to demonstrate to us how to set up and carry out labs for biology class in the future. From this lab, I learned to do an experiment with controls which helps me understand the concept of creating and doing an experiment using controls, dependent variables, independent variables, and constants. Based on my experience from this lab, I now am able to create experiments and labs for other classes but most importantly for all my science classes to come.