Changes

An Indicator is a substance which turns different colors in the presence of [[acid]]s and [[base]]s.  Cabbage water is a common indicator, and is often used in simple acid/base experiments.

An '''indicator''' is a substance which turns different colors in the presence of [[acid]]s and/or [[base]]s.  Cabbage water is a common indicator, and is often used in simple acid/base experiments.

''Litmus'' is one name for a lichen, whose extracts turn red in the presence of acids and blue in the presence of bases. Paper soaked in litmus extracts are used in traditional test for detecting acidity or alkalinity. The phrase ''litmus test'' has become part of the language, often in a social or political context.

''Litmus'' is one name for a lichen, whose extracts turn red in the presence of acids and blue in the presence of bases. Paper soaked in litmus extracts are used in traditional test for detecting acidity or alkalinity. The phrase ''litmus test'' has become part of the language, often in a social or political context.

In serious chemistry, indicators have largely been displaced by glass-electrode [[pH meters]], which measure the pH electronically to much greater accuracies than indicator dyes.

In serious chemistry, indicators have largely been displaced by glass-electrode [[pH meters]], which measure the pH electronically to much greater accuracies than indicator dyes.