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.
Excel is a spreadsheet developed by Microsoft but is by no means the first spreadsheet.   The very first spreadsheet was developed (or invented) by Dan Bricklin and Bob Fraâ¦nkston called VisiCalc. VisiCalc was a spreadsheet written to operate on the Apple II computer and was released in 1979.