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.
12.2g of magnesium reacts completely with oxygen gas. Calculate the mass of oxygen consumed during the reaction and the mass of magnesium oxide produced. 1  Wite the balanced chemical equation: 2Mg (s) + O 2(g) â 2MgO (s). 2  Determine the mole ratio from the equation, Mg: O 2: MgO is 2:1:2.3  Use the mole ratios to calculate the mass of each reactant and product as shown below:iven a mass of m grams of magnesium: 1  mass O 2 = moles(O 2) x molar mass(O 2). & 2 nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp Calculate moles Mg = mass(Mg) &divide molar mass(Mg) = m &divide 24.31. & 3 nbsp &nbsp &nbsp &nbsp &nbsp &nbsp &nbsp Use the balanced chemical equation to determine the mole ratio O 2 :Mg 1:2.