Lewis acids and bases Lewis acids and bases A Lewis acid is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any species that has a filled orbital containing an electron pair which is not involved in bonding but may form a dative bond with a Lewis acid to form a Lewis adduct. For example, NH is a Lewis base, because it can donate its lone pair of electrons. Trimethylborane (MeB) is a Lewis acid as it is capable of accepting a lone
Internet-related prefixes as a cultural reference to the rising popularity at that time of the prefix in product names. The word "virtual" is used in a similar way to the prefixes above, but it is an adjective instead of a prefix. For example, it is used in the terms "virtual reality", "virtual world", and "virtual sex". These prefixes are productive. Michael Quinion notes that most of these formations are nonce words that will never be seen again. He writes that new terms such as "e-health" are unneeded; in this case "telemedicine" already exists to describe the application of telecommunications to medicine. He