Procedure first you will be seeing how a drop of each

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Procedure First, you will be seeing how a drop of each of the reagents wicks through paper. SAVE THE PAPER TOWEL USED IN EACH STEP FOR LATER STEPS. 1. Fold a white paper towel so that it is four layers thick and flatten it. 2. Drop 1 drop of acid (0.1M HCl) onto a paper towel, wait one minute, then measure how far it wicked out into the paper towel. Record the diameter of the drop in Table 1.1 in mm. 3. Repeat Step 2 but use a drop of base (0.1M KOH) instead. 4. Repeat Step 2 but use a drop of bromothymol blue (BTB) instead. NOTE: This is a solution of 99.96% water and 0.04% BTB. a. When you measure the diameter of the BTB drop, you will notice that the BTB color is not evident out as far as the liquid wicks. That is, it appears that the BTB is retained by the paper while the water is relatively free to keep wicking outward. Record (in Table 1.1) both the total diameter of the wet spot and the smaller diameter of the BTB-colored NOTE TO STUDENTS: This is a dry lab. You are only expected to perform the portions of this lab that do not require you to use laboratory equipment or supplies. When appropriate, sample data may be supplied in the lab’s data tables to help you answer the questions.
2 Apex Learning: Chemistry Labs Copyright © 2017 Quality Science Labs, LLC region within the wet spot. b. Also, record what happened to the color of the bromothymol blue as it remained on the paper in contrast to its color in the bottle. Second, you will see what happens when BTB is added to the drop of acid or base. 1. To your drop of acid that wicked into the paper towel, add 1 drop of BTB. Record the color in Table 1.2. 2. To your drop of base that wicked into the paper towel, add 1 drop of BTB. Record the color in Table 1.2.

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