Lewis Acid-Base Concept. The Lewis theory classifies a substance as an acid if it acts as an electron-pair acceptor and as a base if it acts as an electron-pair donor. Other ways of classifying substances as acids or bases are the Arrhenius concept and the Bronsted-Lowry concept.ewis Acid-Base Concept. The Lewis theory classifies a substance as an acid if it acts as an electron-pair acceptor and as a base if it acts as an electron-pair donor. Other ways of classifying substances as acids or bases are the Arrhenius concept and the Bronsted-Lowry concept.
Microsoft Excel was created by Microsoft Corporation. It was first released in 1985.
Cessna Citation Excel. The Cessna Citation Excel (Model 560XL) is a turbofan-powered, medium-sized business jet built by the Cessna Aircraft Company in Wichita, Kansas, United States. A member of the wide-ranging Citation brand of business jets, the Excel was evolved into the Citation XLS and then the Citation XLS+ models.