The number of moles of hydrogen gas present in a 1,500 mL container at 298 K and 2.0 atm pressure is?

Use PV = nRT and solve for n = number of mols.

To determine the number of moles of hydrogen gas, we can use the ideal gas law equation:

PV = nRT

Where:
P = pressure (in atmospheres)
V = volume (in liters)
n = number of moles
R = ideal gas constant (0.0821 L·atm/(mol·K))
T = temperature (in Kelvin)

First, let's convert the given volume to liters:
1,500 mL = 1,500 mL * (1 L / 1,000 mL) = 1.5 L

Now, we can substitute the values into the equation:

(2.0 atm) * (1.5 L) = n * (0.0821 L·atm/(mol·K)) * (298 K)

Simplifying the equation:

3.0 = n * 24.4418

Divide both sides of the equation by 24.4418 to solve for n:

n = 3.0 / 24.4418 ≈ 0.1228 mol

Therefore, the number of moles of hydrogen gas present in the 1,500 mL container at 298 K and 2.0 atm pressure is approximately 0.1228 moles.