Answer: I think you have to subtract the distances
Explanation:
Water and salt, since the salt has dissolved into the water, assumingly, and sand isn't dissolvable so it can't pass through. If the water were to dry up, then you'd get the salt back, then it won't be able to go through the filter
To determine the molar mass of the unknown gas, we use Graham's Law of Effusion where it relates the effusion rates of two gases with their molar masses. It is expressed as r1/r2 = √M2/M1. We calculate as follows:
Let 1 = argon gas 2 = unknown gas
r2 = 0.91r1r1/r2 = 1/0.91
1/0.91 = √M2/M1 = √M2/40M2 = 48.30 g/mol
If 1mol ------- is ----------- 6,02×10²³
so x ------- is ----------- 1,39×10²⁴