Toss the beef with 1/2 teaspoon each salt and pepper. Heat the oil in a pressure cooker over medium-high heat. Add the beef and cook, stirring occasionally, until browned on all sides, about 4 minutes.Add the onions and cook, stirring frequently, until the onions soften and begin to brown, about 4 minutes.eat the oil in a pressure cooker over medium-high heat. Add the beef and cook, stirring occasionally, until browned on all sides, about 4 minutes. Add the onions and cook, stirring frequently, until the onions soften and begin to brown, about 4 minutes.
Thus, metals have positive electron affinities. In the Periodic Table, electron affinity increases (becomes more negative) from left to right in a period. Electron affinity decreases from top to bottom in a Group.
Nitrogen is an anomaly and does not follow the general trend for affinity, as it has an extremely low/not stable value for its first electron affinity, due to its orbital stability (p 3). Electron affinity is defined as the amount of energy released when an atom gains an electron in order to for a negative anion. This is an exothermic process, and therefore the data values included in the simulation are denoted with a negative (-) sign.