Answer:
30 atoms.
Step-by-step explanation:
Based on law of conservation of proportion the atoms we have in reactants = atoms we have in products.
One molecule of glucose contains 6atoms of C, 12 atoms of H and 6 atoms of O, that is:
6+12+6 = 24 atoms
And 3 molecules of Oxygen are 6 atoms. The total atoms in reactants are:
24+6 = 30 atoms = atoms in products