Science Experiment
... 2. Pour 5ml of vinegar from the beaker into the labeled buret. Rinse the walls of the buret thoroughly with the vinegar. Allow vinegar to drain through the stopcock into the 50ml beaker for waste. 3. Fill the buret with vinegar above the zero mark. Withdraw enough vinegar to remove the air from the top of the buret and bring the liquid level into the graduated region of the buret. 4. Repeat steps 2-3 with the sodium hydroxide in the labeled buret. 5. Record initial readings of both burets estimating the volumes to the nearest .01ml 6. Allow about 10ml of vinegar to flow into a clean flask. Add about 10ml of distilled water to the flask to increase the volume. This procedure will make it easier to determine the color change when the endpoint is reached. Ad one or two drops of phenolphthalein solution to serve as an indicator. 7. Titrate the vinegar with the standard solution of sodium hydroxide. Continually swirling the flask. Stop frequently to wash down the sides of the flask with distilled water from your wash bottle. Add the sodium hydroxide drop by drop near the end of the titration until the last drop keeps the solution a pink color the remains after swirling. 8. Add successive quantities of both solutions, drop by drop, going back and forth from pink to colorless until the endpoint is clearly established. Record your data of the final buret readings of both solutions. 9. Discard the liquid in the flask in the disposal container. Rinse the flask thoroughly with distilled water and repeat titration two more times, follow steps 5-8. Data: Trial Number Initial NaOH reading (ml) Final NaOH reading (ml) Initial Vinegar reading (ml) Final Vinegar reading (ml) 1 50ml 5ml 2 50ml 5ml 3 50ml 5ml 4 50ml 5ml Observations: The color indicator during this experiment was very difficult to detect because you wanted to stop it right when the color changed to pink and the pink was extremely faint and hard to tell. Then when the color changed back it took along time but when it did change it was within one drop. Analysis and Interpretation Conclusion Questions: 1. 2. It is important that company’s manufacturin...