Question

the substances that are present on left side of a chemical equation are called

Answer 1

chemical reactants are present on left side of equation and at the right side products are present

Answer 2

hey there ..

they r Reactants 

ex : 2FeSO₄→Fe₂O₃ + SO₂+ SO₃
     (reactants)        ( products) 

hope it helps
       ^-^