What does a pH of 7 indicate about a substance?
pH is just a parameter to indicate the activity of hydrogen ions, or the potential of hydrogen. In other words, it is used in measure the acidity or alkalinity of a substance. Generally, pH ranges from pH 0 to 14. pH less than 7 means the number of free hydrogen ions is more than the number of free hydroxide ions. Closer to pH 0, the difference is more greatly. And pH more than 7 means the opposite things. So, pH 7 is placed in the middle and means neutral. For example, pure water is pH 7. It have the equal amount of free hydrogen ions and hydroxide ions inside. But, pH cannot be used to indicate the reactivity of the substance.
