4Na + O2 = 2Na2O if you use 18 grams of O2 how many grams of Na will you have to also use to make the reaction work​

the correct answer is option d

explanation:

i was wrong its d because they dont use cm when calculating square roots

it's c (engineer's do their work with mechanical stuff not on any living being)

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.