Acid Rain

In APES after school we did an experiment that was testing smoke and acidic gasses in air. We each got to do our own little experiment. So we had to wear gloves and get a small plastic container. Next we used Bromthymol blue indicator solution (10 drops) after pouring distilled water, after that we took matches and dropped it into our plastic container. Then we swirled it around a couple times and attached a tube to a syringe. Once this step was cleared, we had to observe what it was that "changed" the color of the water. After that we wrote down observations and the pH. This part was interesting because we had to suck air from outside or inside using the syringe and had to place it into our container. While doing this the water would bubble.
My mixture was initially blue with a pH of 7.6. After I added the match it changed into an aqua color. The pH went down to a 7. The second part of the experiment was to take inside/outside air. I used the air in Ms. Reid's room but nothing happened. What I understood from this was that the air in Ms. Reid's room has a low amount of acidic gases. Other people got different results. I think the reason behind this was that perhaps the air they were using had a slightly different acidity to it. Or maybe when they first put the match into the container, some smoke got out or maybe they captured enough. If it hadn't been raining out, the air would have been different. Also if we all went outside to a particular location, the air could have had a different reading causing our end result to change entirely.