Please mark me brainiest!
The reason why you don’t see solid or liquid oxygen is because oxygen is a natural occurring gas. Gas can not be solid or liquid because there is too much energy to have volume/shape. That’s why you see oxygen tanks, as the tank keeps the gas contained and that is why you can’t see it in the air outside or in something like H20 (water).
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Answer: Melatonin has been used safely for up to 2 years in some people. However, it can cause some side effects including headache, short-term feelings of depression, daytime sleepiness, dizziness, stomach cramps, and irritability. Do not drive or use machinery for four to five hours after taking melatonin.
The relative molecular mass of the gas : 64 g/mol
<h3>Further explanation</h3>
Given
Helium rate = 4x an unknown gas
Required
The relative molecular mass of the gas
Solution
Graham's Law

r₁=4 x r₂
r₁ = Helium rate
r₂ = unknown gas rate
M₁= relative molecular mass of Helium = 4 g/mol
M₂ = relative molecular mass of the gas
Input the value :

Is the something missing from the question