What's Happening in Erie County. 1  September 1 - September 30 : Agricultural Districts Open Enrollment Period. 2  September 4 : Erie County Government offices are closed today. 3  September 5 : Justice Assistance Grant (JAG) Public Notification - Fiscal Year 2017.
Definition. 1  As a noun, the common definition of chemical is a substance that is produced or used in a process (reaction) involving changes to atoms or molecules. 2  As an adjective, chemical means of or pertaining to chemistry.
From a practical standpoint, inorganic chemicals are substances of mineral origin that do not contain carbon in their molecular structure and are typically based on the most abundant chemicals on earth: oxygen, silicon, aluminum, iron, calcium, sodium, potassium and magnesium.