Commutator (electric) A commutator is a moving part of a rotary electrical switch in certain types of electric motors and electrical generators that periodically reverses the current direction between the rotor and the external circuit. It consists of a cylinder composed of multiple metal contact segments on the rotating armature of the machine.
The word equation that would represent the formation of lithium oxide from lithium metal and oxygen is: lithium + oxygen to lithium oxide. In chemical symbols, the balanced chemical equation is expressed as: Li + O2 = Li2O.
Because alkali metals are so active, the product of their reaction with oxygen gas is not what you might expect. While lithium metal reacts with oxygen gas to form lithium oxide, as one might expect: 4 Li(s) + O2 (g) â 2 Li2O(s) ,