How many electron(s) is (are) needed to complete hydrogen's outer shell.

Stage in which a star’s outer layers have started to cool and grow outward?

Consider the following reactions. (note: (s) = solid, (l) = liquid, and (g) = gas.) mg(s) + ½o2(g) → mgo(s) + 146 kcal/mole h2(g) + ½o2(g) → h2o(g), δh = -57.82 kcal/mole what type of reaction is represented by the previous two examples?

Is a pencil falling to the floor anon contact force, a force, or a contact force