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.
Apple's core product lines are the iPhone smart phone, iPad tablet computer, iPod portable media players, and Macintosh computer line. Founders Steve Jobs and Steve Wozniak created Apple Computer on April 1, 1976, and incorporated the company on January 3, 1977, in Cupertino, California.