First, we need to calculate the rate of diffusion for both gases using Graham's law of diffusion:
Rate of diffusion = Volume / Time
For unknown gas Q:
Rate of Q = 20 cm3 / 12.6 s = 1.587 cm3/s
For oxygen gas:
Rate of O2 = 10 cm3 / 11.2 s = 0.893 cm3/s
Next, we can calculate the relative rate of diffusion for both gases:
Relative rate of diffusion = Rate of unknown gas / Rate of oxygen gas
Relative rate of diffusion = 1.587 cm3/s / 0.893 cm3/s = 1.7771
According to Graham's law of diffusion, the relative rate of diffusion is inversely proportional to the square root of the molecular mass of the gas. Therefore, we can set up the following equation:
√Molecular mass of O2 / √Molecular mass of Q = 1.7771
√16 / √Molecular mass of Q = 1.7771
4 / √Molecular mass of Q = 1.7771
√Molecular mass of Q = 4 / 1.7771
√Molecular mass of Q = 2.2506
Molecular mass of Q = (2.2506)2
Molecular mass of Q = 5.063
Therefore, the molecular mass of the unknown gas Q is approximately 5.063.
20cm3 of an unknown gas Q takes 12.6 seconds to pass through small orifice.10cm3 of
oxygen gas takes 11.2 seconds to diffuse through the same orifice under the same
conditions of temperature and pressure .Calculate the molecular mass of unknown gas Q
( O=16)
1 answer