Question

) The student collects the H2(g) produced by the reaction and measures its volume over water at 298 K after carefully equalizing the water levels inside and outside the gas-collection tube, as shown in the diagram below. The volume is measured to be 45.6mL . The atmospheric pressure in the lab is measured as 765 torr , and the equilibrium vapor pressure of water at 298 K is 24 torr . (i) The pressure inside the tube due to the H2(g)

Answer 1

Answer:

P (H₂) = 741 torr

Explanation:

Let's begin by listing out the given parameters:

Temperature (water) = 298 K, volume = 45.6 mL,

atmospheric pressure, P (total) = 765 torr, vapor pressure of water, P (H₂O) = 24 torr

To get the pressure of inside the tube, P (H₂), we apply Dalton's Law of Partial Pressure and we have:

P (total) = P (H₂) + P (H₂O)

P (total) = 765 torr, P (H₂O) = 24 torr

P (H₂) = P (total) - P (H₂O) = 765 - 24

P (H₂) = 741 torr

It therefore becomes clear that the pressure of H₂(g) is 741 torr