What would you expect the difference to be in the rate of diffusion of vinegar (molecular weight about 60) compared to oxygen (molecular weight about 32)?

Vinegar has slower rate of diffusion due to higher mass.

Explanation:

The rate of diffusion in vinegar is slower than oxygen because of the higher mass of vinegar. Vinegar has molecular weight about 60 while on the other hand, oxygen has molecular weight about 32 so vinegar has more weight than oxygen which causes slow diffusion of vinegar from one place to another as compared to oxygen whose rate of diffusion is higher due to its lower weight.

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