Respuesta :
A, 2 molcules
H2O is one molecule, it has 3 atoms (two hydrogen and one oxygen)
2 H2O are two water molecules
H2O is one molecule, it has 3 atoms (two hydrogen and one oxygen)
2 H2O are two water molecules
There are three total molecules in H2O, but the two represents the number of Hyrdogen molecules. So the 2 represents 2 molecules