Question

Given the equation 2mg(s) + o2(g) → 2mgo(s) + 72.3 kj, how much heat is involved in the production of 5.0 mol of mgo? question 2 options: 36kj 180 kj 510 kj 360 kj

Answer 1

The heat is involved   in the  production of 5.0 mol of MgO  is   180 Kj

               calculation

2 Mg (s)   +O2 → 2 MgO

From  the  equation  above two  moles    of MgO  is used  therefore   

72.3   is for   2   moles

that is   72.3  kj =  2moles
                  ?      = 5  moles 

by  cross  multiplication

= 72.3  kj × 5/2     = 180  Kj