Urine Reaction Experiment: Is Phenolphthalein Solution Turn Red When It Comes Into Contact With Urine?

Urine contains ammonia. Since phenolphthalein solution turns red when it meets ammonia gas, phenolphthalein solution will turn red when urine and phenolphthalein solution meet. It can be hypothesized that a phenolphthalein solution turns red when it comes into contact with urine. In this project, we check the hypothesis through experiments. 

We need urine, phenolphthalein solution, and a petri dish for the experiment. However, since there is no Petri dish, a household dish was used in the experiment. 

Add 3-5 drops of phenolphthalein solution to the center of the Petri dish. The picture above is a picture of when the phenolphthalein solution is dropped into the center of the dish. 

Add 1-2 drops of urine to the phenolphthalein solution in the center of the Petri dish. The picture above is a picture of when urine is dropped into the phenolphthalein solution in the center of the dish.

Observe the color change of the phenolphthalein solution. The picture above is a picture of when 5 minutes have passed since urine was dripped into the phenolphthalein solution. Looking at the picture above, it can be seen that the phenolphthalein solution and urine did not turn red even though they met. 

When we did an experiment, phenolphthalein solution and urine met but did not turn red, so that the hypothesis was wrong. Therefore, we conclude that phenolphthalein solution does not turn red when it comes into contact with urine.