Question

Oxygen gas was produced in a reaction and collected over water. A 136.1 mL mL sample of gas was collected over water at 25C and 1.06 atm. The vapor pressure of water is 23.76 mmHg at 25C. Find the mass of ocygen gas collected in a reaction and collected over water. A 136.1 mL sample of gas was collected over water at 25C and 1.06 atm. The vapor pressure of water is 23.76 mmHg at 25C. Find the mass of oxygen gas collected.

Answer 1

Step-by-step explanation:

We shall find volume of gas at NTP or at 273 K , 760 mm of Hg .

Pressure of given gas = 1.06 x 760 mm of Hg less vapor pressure of water .

= 805.6 - 23.76 = 781.84 mm of Hg

For it we use gas law formula ,

P₁V₁ / T₁ = P₂V₂ / T₂

781.84 x 136.1 / ( 273 + 25 ) = 760 x V₂ / 273

= 128.26 mL .

= 128.26 x 10⁻³ L .

22.4 L of oxygen will have mass of 32 g

128.26 x 10⁻³ L of oxygen will have mass of 32 x 128.26 x 10⁻³ / 22.4 g

= 183.22 mg .