how many molecules of h2o if formed from this equation Al2O3 + 3H2 ->2Al + 3H2O
Depends upon how much Al2O3 and/or H2 you started with.
There are 149 molecules of Al2O3
To determine the number of molecules of H2O formed from this equation, we need to use stoichiometry and the concept of mole-to-mole ratios.
In the balanced chemical equation:
Al2O3 + 3H2 -> 2Al + 3H2O
The coefficient in front of H2O is 3, which means that for every three moles of H2O formed, we would need one mole of Al2O3.
Given that you haven't provided the amount of Al2O3 or H2, I will assume that we have excess Al2O3 and H2. Therefore, we need to determine the moles of H2O formed when we have an arbitrary amount of Al2O3 and H2.
Let's assume we have 1 mole of Al2O3. Based on the balanced equation, we can see that we would obtain 3 moles of H2O.
Now, the number of water molecules in one mole of H2O is approximately 6.02 x 10^23 (Avogadro's number). Therefore, in 3 moles of H2O, we would have:
3 moles * 6.02 x 10^23 molecules/mole = 1.806 x 10^24 molecules of H2O.
So, if 1 mole of Al2O3 is used, you would obtain approximately 1.806 x 10^24 molecules of H2O.
Keep in mind that the actual number of H2O molecules formed will depend on the amount of starting materials (Al2O3 and H2) and the reaction conditions.