# How Math is used to Describe Change

Mathematics is used, in a variety of ways, to describe and measure change. One of the most common ways to describe change is to use a graph, which is a visual representation of a mathematical expression. For example, by graphing the speed of a vehicle vs. time, one can easily observe the changes in speed by looking at the slope of the line on the graph.

In chemistry, starting materials and end products are measured before, during, and after a reaction is taking place. Then, the rate of the reaction can be determined, the materials that limit the reaction rate can be determined, and the activation energy needed to start the reaction, or if a chemical reaction occurred at all. The Henderson-Hasselbalch Equation is used to predict the changes in pH in a solution, when acids or bases are added.

In biology, changes in the composition of populations of living organisms can be measured and described mathematically. The Hardy-Weinberg equation assists biologists in measuring and predicting the changing frequencies of genetic traits in populations.
The changing growth rate, of bacteria and a myriad of living organisms, including humans, is measured and described my mathematics placed on graphs and charts. Statistics is then applied to the results of the observed changes, to determine if the changes described are significant changes, or if the changes are because of natural variations in the data that comes from methods used in the collection of the data.

In weather forecasting, mathematics is used to describe the changing conditions. A whole branch of mathematics, chaos theory, was developed from use of mathematics to describe the many changes occurring at the same time in complicated systems, such the Earth’s continually changing weather. Math is used to make accurate maps. Changing geographical features and geological features can be observed by comparing maps of the same area that have been charted at different dates over a period of time.

The changing stock market is mathematically described by charts, averages, and graphs. A person’s portfolio investments are described in a pie chart and the percentages of the money invested. Math is even used to describe and measure time because clocks and watches have precisely measured gears that are described by the hands on the faces of these time pieces. In some modern ways to measure time, math is used to describe the vibration of an atom. Now, I will spell check this article and get the statistics that describe the number of words and the reading level of what I have written.