In anatomy, the second cervical vertebra of the spine is named the axis or epistropheus. By the atlanto-axial joint, it forms the pivot upon which the first cervical vertebra, which carries the head, rotates. The most distinctive characteristic of this bone is the strong odontoid process known as the dens which rises perpendicularly from the upper surface of the body. That peculiar feature gives to the vertebra a rarely used third name: vertebra dentata. In some judicial hangings the odontoid pr
1 An acid-base reaction is type of double displacement reaction that occurs between an acid and a base. 2  The H + ion in the acid reacts with the OH-ion in the base to form water and an ionic salt: 3  HA + BOH â H 2 O + BA. 4  The reaction between hydrobromic acid (HBr) and sodium hydroxide is an example of an acid-base reaction: Direct Combination or Synthesis Reaction. 2  In a synthesis reaction two or more chemical species combine to form a more complex product. 3  A + B â AB. 4  The combination of iron and sulfur to form iron (II) sulfide is an example of a synthesis reaction :
2. When the reaction is between an acid (any compound that forms hydrogen ions) and a base (any compound that forms hydroxide ions), water is formed as one of the products. This is called neutralization. An example of a neutralization reaction is seen in the reaction above between sulfuric acid and sodium hydroxide.5. chemical reaction is the process in which atoms present in the starting substances rearrange to give new chemical combinations present in the substances formed by the reaction. These starting substances of a chemical reaction are called the reactants, and the new substances that result are called the products.