Calculate the amount of water substance that is formed as a result of heating an aluminum hydroxide weighing 15.6 g.

Aluminum hydroxide is an unstable substance that decomposes when heated to a certain temperature.
To find the amount of water substance as a reaction product, first we will compose it:
2Al (OH) 3 => Al2O3 + 3H2O
We make the proportion:
15.6 – x
2 * 78 – 3 * 18
Where: x = 15.6 * 3 * 18/2 * 78 = 5.4 grams
Next, we need to find the amount of water substance. To do this, we divide the mass of the resulting water by its molar mass.
v (H2O) = 5.4 grams / 18 g / mol = 0.3 mol. Answer: The amount of water substance is 0.3 mol.