Base (chemistry) Base (chemistry) In chemistry, bases are substances that, in aqueous solution, release hydroxide (OH) ions, are slippery to the touch, can taste bitter if an alkali, change the color of indicators (e.g., turn red litmus paper blue), react with acids to form salts, promote certain chemical reactions (base catalysis), accept protons from any proton donor or contain completely or partially displaceable OH ions. Examples of bases are the hydroxides of the alkali metals and the alkaline earth metals (NaOH, Ca(OH), etc., see alkali hydroxide and alkaline earth hydroxide). These particular substances produce hydroxide ions (OH) in aqueous solutions, and are
Chemistry: A Volatile History Just 92 elements combine to form all the compounds on Earth. Iron, when combined with chromium, carbon and nickel makes stainless steel. Glass is made of silicon and oxygen. Since prehistoric times, people have been engaging in ‘bucket chemistry’ – adding all sorts of chemicals together, just to see what would happen. As a result, many early discoveries in chemistry were accidental. In 18th century Prussia, Heinrich Diesbach was trying to produce a synthetic red paint. He started by heating potash (potassium carbonate), with no idea that his potash had been contaminated with blood. When heated, the proteins in blood