Chemistry it is dissolved in water, and a base is one that produces hydroxide ions when dissolved in water. According to Brønsted–Lowry acid-base theory, acids are substances that donate a positive hydrogen ion to another substance in a chemical reaction; by extension, a base is the substance which receives that hydrogen ion. A third common theory is Lewis acid-base theory, which is based on the formation of new chemical bonds. Lewis theory explains that an acid is a substance which is capable of accepting a pair of electrons from another substance during the process of bond formation, while a base is
NASA Star and Exoplanet Database NASA Star and Exoplanet Database The NASA Star and Exoplanet Database (NStED) is an on-line astronomical stellar and exoplanet catalog and data service that collates and cross-correlates astronomical data and information on exoplanets and their host stars. NStED is dedicated to collecting and serving important public data sets involved in the search for and characterization of exoplanets and their host stars. The data include stellar parameters (such as positions, magnitudes, and temperatures), exoplanet parameters (such as masses and orbital parameters) and discovery/characterization data (such as published radial velocity curves, photometric light curves, images, and spectra). The NStED collects and serves