How many H2O molecules are in 2 mol

A mole of horses would be Avogadro number of horses (a lot actually !). Avogadro number is 6.023 x 10(23). A mole of H (hydrogen) atoms contains 6.023 x 10(23) H atoms. A mole of H2 molecules contains 6.023 x 10(23) H2 molecules or 2 moles of H atoms (since each molecules has 2 atoms).

Explanation:

A mole (mol) is the amount of a substance that contains 6.02 × 10 23 representative particles of that substance. The mole is the SI unit for amount of a substance. Just like the dozen and the gross, it is a name that stands for a number. There are therefore 6.02 × 10 23 water molecules in a mole of water molecules.

Explanation:

it's c. elements are placed in rows based on how may valencies electrons have.

it is b that is the answer.