Ph Lab Essay, Research Paper

What is the pH of the substance?

Controlled Comparison: During class, our instructor set up the same lab that we were doing with 2 solutions, both of which were known acidic or basic. He placed 2ml of the known acid into 2 different test tubes, and 2ml of the known acid into 2 different petri dishes. Then using forceps, he tested blue litmus paper in one petri dish, and red litmus paper in another. The blue litmus paper, after being dipped into the solution, turned red in reaction to the acidic solution. While the red litmus paper remained the same color. Next he used the eye dropper and put 2 drops of phenolphthalein into one of the test tubes, and bromthyol blue into the other test tube. The phenolphthalein turned a deep milky color after reacting to the acid. While the bromthyol blue turned a deep yellow hew. He placed 2ml of the known base into 2 different test tubes, and 2ml of the known base into 2 different petri dishes. Then using forceps, he tested blue litmus paper in one petri dish, and red litmus paper in another. The blue litmus paper, after being dipped into the solution, remained its original color of blue in the basic solution. While the red litmus paper, in reaction to the basic solution quickly turned blue. Next he used the eye dropper and put 2 drops of phenolphthalein into one of the test tubes, and bromthyol blue into the other test tube. The phenolphthalein turned a deep purple like color after reacting to the base. While the bromthyol blue remained the same color of blue.

Materials and Procedure: Using a graduated pipet, take 2ml of one solution and put that into 2 test tubes and 2 petri dishes each with 2ml of solution in them. Now in one petri dish use the plastic forceps and test the red litmus in them. Repeat with the blue litmus in the other petri dish. Now take the eye dropper and put 2 drops of phenolphthalein and drop that into a test tube and record the results. Repeat this with the other test tube and bromthyol blue. After this clean out and wash all test tubes and petri dishes. Now repeat with the remaining solutions.

Data and Observations: My data and observations are contained on an attachment to this sheet. Solution #1 changed the blue litmus but not the red. Also it turned the phenolphthalein milky and the bromthyol blue yellow. Solution #2 changed the red litmus, but not the blue. Also it turned the phenolphthalein purple, but had no effect on the bromthyol blue. Solution #3 changed the red litmus, but not the blue. Also it turned the phenolphthalein purple, but had no effect on the bromthyol blue. Solution #4 changed the blue litmus but not the red. Also it turned the phenolphthalein milky and the bromthyol blue yellow. Solution #5 changed the blue litmus but not the red. Also it turned the phenolphthalein milky and the bromthyol blue yellow.

Analysis and Conclusion: My data table is contained on another sheet of paper attached to this report. After observing the reactions that solution #1 had with our indicators, and comparing them to the known and controlled experiment, that was carried out in front of us, we determined that solution #1 was an Acid. This is because when tested, it turned the blue litmus red, yet the red litmus stayed the same. In reaction to the phenolphthalein, it became milky, while with the bromthyol blue it became a yellow looking color. After observing the reactions that solution #2 had with our indicators, and comparing them to the known and controlled experiment, that was carried out in front of us, we determined that solution #2 was a Base. This is because when tested, it turned the red litmus blue, yet the blue litmus stayed the same. In reaction to the phenolphthalein, it became purple, while with the bromthyol blue it had no color change. After observing the reactions that solution #3 had with our indicators, and comparing them to the known and controlled experiment, that was carried out in front of us, we determined that solution #3 was a Base. This is because when tested, it turned the red litmus blue, yet the blue litmus stayed the same. In reaction to the phenolphthalein, it became purple, while with the bromthyol blue it had no color change. After observing the reactions that solution #4 had with our indicators, and comparing them to the known and controlled experiment, that was carried out in front of us, we determined that solution #4 was an Acid. This is because when tested, it turned the blue litmus red, yet the red litmus stayed the same. In reaction to the phenolphthalein, it became milky, while with the bromthyol blue it became a yellow looking color. After observing the reactions that solution #5 had with our indicators, and comparing them to the known and controlled experiment, that was carried out in front of us, we determined that solution #5 was an Acid. This is because when tested, it turned the blue litmus red, yet the red litmus stayed the same. In reaction to the phenolphthalein, it became milky, while with the bromthyol blue it became a yellow looking color.