The results confirmed my hypothesis that solutions with lower pH freeze at lower temperatures than solutions with higher pH. After researching my topic, however, I realized that salt water, pH 7, also froze at a lower temperature than pure water.
To investigate this I repeated the process but used 2.5mL of salt and sugar dissolved in two different beakers of 200mL of water. I placed these as well as a beaker of pure water and a beaker with 2.5ml citric acid solution in the freezer. I discovered that all the solutions had lower freezing points than water. My conclusion is anything dissolved in water changes its freezing point.