mole 4dMoles, known medically as melanocytic nevi are due to a proliferation of pment cells known as melanocytes. They are common, being present in everyone and can appear anywhere on2A+4B 3C+4D. 5 6. Limiting reactant is declared which have lowest ratio of . coefficient. Moles. for reactant. For A: 2. 5 =2.5. For B: 4. 6 =1.5. ⇒B is limiting reagent.