Question #0fc8e

1 Answer
Jul 1, 2017

Answer:

#3# atoms.

Explanation:

As its chemical formula suggests, a molecule of water contains

  • two atoms of hydrogen, #2 xx "H"#
  • one atom of oxygen, #1 xx "O"#

This means that a single molecule of water contains a total of #3# atoms.

#"no. of atoms in H"_2"O" = "2 atoms of H + 1 atom of O"#

#"no. of atoms in H"_2"O" = "3 atoms"#

https://www.dreamstime.com/stock-photography-molecule-water-h2o-image6468242

So remember, we use subscripts to denote the number of atoms of each element present in a given compound. Keep in mind that we do not add a subscript of #1# when dealing with a single atom.

So in this case, two atoms of hydrogen are shown by adding a subscript of #2# after #"H"#. The single atom of oxygen is shown by adding the chemical symbol of oxygen without a subscript of #1#.

So instead of

#"H"_2"O"_1#

we have

#"H"_2"O"#