A zero-order process is a process that has a constant rate. The rate of the zero-order process does not depend on the amount of the reactant involved in the process.

For example, if the elimination of a drug follows zero-order kinetics, this means that there is a constant amount of the drug eliminated per unit time, regardless of the amount of the drug in the body.

The negative sign (-) is used because the amount of the drug is decreasing.

A zero-order process is a process that has a constant rate. The rate a the zero-order process is the zero-order rate constant and it does not depend on the amount of the reactant involved in the process.

For example, when the drug elimination follows zero-order kinetics, the amount of the drug eliminated per unit time is constant and is equal to the zero-order rate constant.

In this case, the zero-order rate constant has units, of amount/time.

The slope of a straight line is the rate of change of the dependent variable (the variable plotted on the Y-axis) relative to the change of the independent variable (the variable plotted on the X-axis). A straight line has one slope (constant slope), however the slope of a curve is changing at different points on the curve.

To determine the slope of a straight line, take two points on the line and determine the X and Y coordinates of each of these points. The slope can be determined from the following relationship: