Question

Which of the conversion factors below is the "center piece" or middle step of every stoichiometry problem?

A) Molar Volume
B) Molar Mass
C) Mole ratio
D) Avogadro's Number

Answer 1

C :  Mole Ratio

here is the reason whenever we start giving answer if any question of stoichiometry problem ( how much reacted produced yield % ) these are steps 
1 . write the balanced equation 
2    Convert everything given to moles 
3.   determine limiting reagent '
4.    Convert mole limiting reagent to mole 
 other species
5.      convert moles to mass 
6.     %yield =  (  actual mass / theoretical mass ) * 100% 

Coefficient of balanced equation are mole ratio