Abscissa
Definition and meaning of Abscissa in chemistry.
The abscissa is the horizontal coordinate of a point on a graph, its distance measured along the x-axis. It is paired with the ordinate, which is the vertical (y-axis) coordinate.
In more detail
When chemical data are plotted, the abscissa usually shows the independent variable, the quantity the experimenter controls, such as time, temperature, or concentration, while the ordinate shows the measured response. Reading a graph correctly depends on knowing which quantity is plotted on each axis.
Key facts
| Axis | Horizontal (x-axis) |
|---|---|
| Paired with | Ordinate (y-axis) |
| Usually shows | The independent variable |
On a graph of reaction rate against temperature, temperature is plotted on the abscissa (x-axis) and rate on the ordinate (y-axis).
Frequently asked questions
What is the difference between abscissa and ordinate?
The abscissa is the horizontal x-axis coordinate; the ordinate is the vertical y-axis coordinate of the same point.