If you ever swam in a pool and your eyes began to sting and turn red, you felt the effects of an incorrect ph level. ph measures the concentration of hydronium ions and can be modeled by the function p(t) = −log10t. the variable t represents the amount of hydronium ions; p(t) gives the resulting ph level.
water at 25 degrees celsius has a ph of 7. anything that has a ph less than 7 is called acidic, a ph above 7 is basic, or alkaline. seawater has a ph just more than 8, whereas lemonade has a ph of approximately 3.