21. A picture emerged of metals as positive ions held together by an ocean of negative electrons. 22. Sodium is the primary cation ( positive ion ) in extracellular fluids in animals and humans. 23. The positive ions created in the avalanche induce a positive current signal on the pad plane. 24. They are composed of positive ions whose identity depends on the residual gas inside the tube. 25. Acid is a substance that produces hydrogen ions, the only positive ions when dissolved in water. 26. These ions react with a sample surface to make positive ions that are used in mass spectroscopy. 27. There is some belief the winds also create positive ions , which are believed to affect mood negatively. 28. These struck further gas atoms, knocking electrons off them, creating more positive ions in a chain reaction. 29. These collide with atoms of the gas, knocking electrons off of them and creating more positive ions . 30. In a metal, atoms readily lose their outermost ( " valence " ) electrons, forming positive ions .
