<prompt> Which is wrong regarding entonox?Is used for labor analgesiaIs a mixture of nitrous Oxide and oxygen in the ratio of 50: 50Pin index is 7Can be used for anesthesia  <response>: Entonox is used for analgesia not anesthesia. Entonox Nitrous oxide and oxygen is a colourless, odourless gas made up of half oxygen and half nitrous oxide. Its also known as laughing gas. It can take the edge off labour pain, rather than blocking it out 