What is the volume of oxygen gas (in Liters) that will be produced if 3.5 g H_2O will react at a pressure of 119 kPa and temperature of 35 degrees Celsius?

Question

According that H_2O reacts with Na_2O_2 according to the following equation:

2Na_2O_2 + 2H_2O yields 4NaOH + 1O_2

Answer 1

2Na₂O₂ + 2H₂O ==> 4NaOH + O₂

We first need to find MOLES of O2 produced, and then convert to volume using PV = nRT (Ideal Gas Law)

moles H2O reacting = 3.5 g H2O x 1 mole/18 g = 0.194 moles H2O reacted

moles O2 produced = 0.194 moles H2O x 1 mole O2/2 moles H2O = 0.0972 moles O2 produced

Volume O2 produced: PV = nRT and solve for V, but first convert 119 kPa to atm (119 kPa x 1 atm/101.3 kPa)

V = nRT/P = (0.0972)(0.0821)(308)/1.17 atm

V = 2.1 liters