An acid is a chemical compound that reacts with metals to form salts by releasing hydrogen.
Their general properties are sour taste, the power of changing vegetable blues into reds, of evolving hydrogen in presence of magnesium, of decomposing chalk with effervescence, and of being in various degrees neutralized by alkalis. An acid has been defined as a compound of hydrogen, the whole or a part of which is replaceable by a metal when this is presented in the form of a hydroxide; being monobasic, dibasic, or tribasic, according to the number of replaceable hydrogen atoms in a molecule. Some acids also contain oxygen and these are called oxy-acids. Varying amounts of oxygen in an acid are reflected in its name ending -ous or -ic, and the salts formed from such acids are similarly named ending in -ite and -ate. Research Acid