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 4.20 mol fe and 6.70 mol nio(oh) react?

3.35 mole.

Explanation:

It is a stichiometriy oriented problem.From the balanced equation: Fe + 2NiO(OH) + 2H₂O → Fe(OH)₂ + 2Ni(OH)₂It is clear that 1.0 mole of Fe reacts with 2.0 moles of NiO(OH) to produce 1.0 mole of Fe(OH)₂.Fe reacts with NiO(OH) with 1:2 ratio.So, 6.70 mole of NiO(OH) will react completely with (6.70 x 0.5 = 3.35 mole) of Fe. But Fe is present in excess (4.20 mole), so the limiting reactant is NiO(OH).

Using cross multiplication and from the stichiometry:

2.0 moles of NiO(OH) produce → 1.0 mole of Fe(OH)₂

6.70 mole of NiO(OH) produce → ??? mole of Fe(OH)₂

∴ The number of moles of Fe(OH)₂ produced = (1.0 mole) *6.70 mole) / (2.0 mole) = 3.35 mole.

Copper, silver, aluminum, cobalt, chromium, mercury 

You would do 1500/4 and the answer is 375