How many molecules are in 2.00 moles of h2o

1 mole is 6.02x10^23. After multiplying this by 2.00, you should get 1.204e24 or 1.204x10^24.

Avogadro says one mole of particles contain 6.02 x 10^23 particles. Hence, 2 moles of water molecules contains 2 x 6.02 x 10^23 molecules.