Respuesta :
Answer:
Explanation:
The balanced equation for the decomposition of water is:
2H2O = 2H2 + 1O2
This tells us that we should expect 1 mole of O2 for every 2 moles of H2O, a molar ratio of (1 O2/2 H2O).
If we start with 2 moles of water, we should get (2mole H2O)*(1 O2/2 H2O) = 1 mole of H2.
But we are given just 20ml of water by the stingy boss. Â We need to calculate the number of moles of water in that 20 ml. Â We'll assume pure water at room temperature, so density = 1g/ml. Â We have 20 g of H2O. Â To find moles, divide by water's molar mass of 18 g/mole:
20g/(18g/mole) = 1.11 moles H2O
The moles of H2 produced would be:
(1.11 moles H2O)*(1 O2/2 H2O) = 0.55 moles O2 produced
We are not given the conditions of temperature and pressure, so the only way the calculate a volume of gas occupied by 1 mole of oxygen is to assume standard temperature and pressure (STP). Â At STP 1 mole of gas occupies 22.4 liters.
1 mole of O2 will be 22.4 liters.
0.55 moles of O2 would be:
(0.55 mole O2)*(22.4 liters) = 12.32 liters