In this analysis, we will be determining the amount of chloride in a solution based upon its complexation with silver. It will form a silver chloride precipitate, which will cause a color change due to phasions reaction. In this titration, it is crucial to add dextrine to each flask. The dextrine can be pre-weight, only weighing about 0.1 grams, and kept in waypapers until ready to be added to each flask. It can be added well in advance of the titration. And no, I did not throw the white paper on the floor. There is, in fact, a garbage on the other side of the desk. After the dextrine has been added to the solution, add additional water to break it up, and ensure that as much of it is dissolved as possible. You can rinse down the sides with the ionized water. The indicator using this titration is dichloroforesine. The indicator can absorb onto the surface of the silver chloride particles, but only when there is no excess chloride present in solution. When all the chloride has been precipitated by the addition of silver, the florescene will then add absorb onto those particles, going from a yellow color to a pink end point color. Your first titration will be a rough titration, where you add the florescene right away. You will then rapidly add titrant to reach the end point, or at least a rough approximation. And the reason for this is that the addition of florescene to the titration flask is detrimental to the proper visualization of the end point. The florescene accelerates the photo reduction of the silver ions, leading to the formation of black particles. These black particles make it difficult to visualize the color change from yellow to pink. For future titrations, you will not add the florescene indicator until you are a couple of milliliters away from this rough end point. All other aspects of the titration are the same. You will add the dextram before doing the titration, you will rinse it down with some dey water, and you will carefully record the volume on the burette before beginning your titration. Since a rough end point is already known for this titration, you can add titrant rapidly until you are a couple of milliliters from that end point volume. Do remember to swirl and occasionally rinse down the sides of your flask. It is so important to maintain proper analytical technique, even though you are going rapidly. Once you are within a few milliliters of the approximate end point, you will want to add the dichloroforecene indicator solution. You only need about four or five drops in order to be able to see the color very nicely in this solution. Now proceed to slowly and carefully add titrant until you begin noticing a pink color up here where the titrant solution reaches the flask. As with other titrations, the longer this end point color persists, the closer you are to the end point. Continue to swirl the flask and rinse down the sides periodically to ensure that all reagents are mixed fully. The color changes subtle and is not very easy to visualize in this video. However, you do want to have the solution change to a pink color, but a very light pink color, not a very dark peptobizmole pink. You may also note that the previous flask used for a titration sitting on the right of the screen has now become more of a grayish pink color. This is because of the photo reduction of the silver in solution, as well as the settling of the particles over time. For this reason, you should not compare your color to the color of previous titrations. There is a significant change over time. Here, you should be able to see that one drop turns the solution to a slightly pink color, removing most of the traces of yellow. For a better comparison, here is a still photo of the end point and the original color of solution, as well as an overshot titration which clearly indicates a two dark pink color.