A homogeneous material with a definite composition. A homogeneous material with a definite composition. If the element is present, it must have either a @value, an @id, or extensions Unique identifier for the substance. For an instance, an identifier associated with the package/container (usually a label affixed directly). A boolean to indicate if this an instance of a substance or a kind of one (a definition). A code to indicate if the substance is actively used. A code that classifies the general type of substance. This is used for searching, sorting and display purposes. A code (or set of codes) that identify this substance. A description of the substance - its appearance, handling requirements, and other usage notes. When the substance is no longer valid to use. For some substances, a single arbitrary date is used for expiry. The amount of the substance. A substance can be composed of other substances. A homogeneous material with a definite composition. The amount of the ingredient in the substance - a concentration ratio. Another substance that is a component of this substance. Active Inactive Entered in Error If the element is present, it must have either a @value, an @id, or extensions