The pH scale ranges from 0 to 14. A pH of 7 is neutral. A pH less than 7 is acidic. A pH greater than 7 is basic. Each whole pH value below 7 is ten times more acidic than the next higher value.
Pure water is neutral.
But when chemicals are mixed with water, the mixture can become either acidic or basic. Examples of acidic substances are vinegar and lemon juice. Laundry detergents and ammonia are examples of basic substances. Chemicals that are very basic or very acidic are reactive. These chemicals can cause severe burns.