Ten simple rules to create a serious game, illustrated with examples from structural biology

Many covalent molecules have central atoms that do not have eight electrons in their Lewis structures. These molecules fall into three categories:

Newton's third law states that every action has an equal and opposite reaction. Consider a swimmer pushing off the side of a pool. They push against the wall of the pool with their feet and accelerate in the direction opposite to that of their push. This occurs because the wall exerts an equal and opposite force on the swimmer. Here, the forces do not cancel out each other as they are acting on different systems. In this case, there are two systems: the swimmer and the wall. If we select...

Solving problems that involve forces is easy using free-body diagrams. A free-body diagram is a sketch showing all the external forces that are acting on an object or system. The object or system is represented by a single isolated point (or free body). Only those forces acting on it that originate outside of the object or system—the external forces—are shown. The forces are represented by vectors extending outward from the free body. Imagine a person sitting on a chair. Here, the...

Chemical bonds are complex interactions between two or more atoms or ions, which reduce the potential energy of the molecule. Gilbert N. Lewis developed a model called the Lewis model that simplified the depiction of chemical bond formation and provided straightforward explanations for the chemical bonds seen in most common compounds.

To determine the electron configuration for any particular atom, we can build the structures in the order of atomic numbers. Beginning with hydrogen, and continuing across the periods of the periodic table, we add one proton at a time to the nucleus and one electron to the proper subshell until we have described the electron configurations of all the elements. This procedure is called the aufbau principle, from the German word aufbau (“to build up”). Each added electron occupies the...

Approximating areas under curved boundaries is a common problem in applied mathematics, particularly when an exact calculation is difficult or impractical. One effective numerical method for this purpose is the Midpoint Rule, which provides an estimate of the area under a curve by using rectangular approximations over a specified interval.Description of the Midpoint RuleThe Midpoint Rule begins by dividing the given interval into a number of equal subintervals. For each subinterval, the...