How many moles are in 7.5 x 10^19 molecules of ammonia, NH3?

Several kinds of bears are found on earth. most bears are brown or black, but one type of bear, the polar bear, is white. what process led to this difference in fur color? explain your answer.

What are the genotypic and phenotypic ratios

In 1901, thomas edison invented the nickel-iron battery. the following reaction takes place in the battery. fe(s) + 2 nio(oh)(s) + 2 h2o(l) fe(oh)2(s) + 2 ni(oh)2(aq) how many mole of fe(oh)2, is produced when 5.35 mol fe and 7.65 mol nio(oh) react?