Answer:
0.67 mole
Step-by-step explanation:
From detailed studies of gases, we have discovered that at stp 1 mole of a gas occupies 22.4L.
With the above discovery, it means that 1 mole of hydrogen gas occupy 22.4L.
Therefore, Xmol of Hydrogen gas will occupy 15L i.e
Xmol of Hydrogen gas = 15/22.4 = 0.67 mole.
Therefore, there are 0.67 mole of Hydrogen gas in 15L of the gas