Question

If 2.18 g of sodium peroxide (Na2O2) react with water to produce sodium hydroxide abs oxygen, how many liters of oxygen will be produced at 17.7 Celsius abs 726 torr?

Answer 1

0.350 L

Step-by-step explanation:

• 2Na₂O₂ + 2H₂O → 4NaOH + O₂

First we convert 2.18 g of Na₂O₂ into moles, using its molar mass:

• 2.18 g ÷ 78 g/mol = 0.0279 mol Na₂O₂

Then we convert 0.0279 moles of Na₂O₂ into moles of O₂, using the stoichiometric coefficients of the reaction:

• 0.0279 mol Na₂O₂ *
  `(1molO_2)/(2molNa_2O_2)` = 0.0140 mol O₂

Finally we use the PV=nRT formula to calculate the volume of oxygen produced:

• P = 726 torr

• V = ?

• n = 0.0140 mol

• R = 62.36 torr·L·mol⁻¹·K⁻¹

• T = 17.7 °C ⇒ 17.7 + 273.2 = 290.9 K

Inputting the data:

• 726 torr * V = 0.0140 mol * 62.36 torr·L·mol⁻¹·K⁻¹ * 290.9 K

• V = 0.350 L