Respuesta :

Answer:

6moles of Mg

Explanation:

The reaction expression is given as:

          BO₃   +    3Mg   →    3MgO    +    B

Given:

Number of moles of B produced  = 2 moles

Unknown:

Number of moles of Mg required  = ?

Solution:

  From the balanced reaction expression:

          1 mole of B is produced from 3 moles of Mg

          2 moles of B will be produced from 2 x 3  = 6moles of Mg