If the outside of your flask is not dry when the first mass determination is made and it is dried for the second mass determination, what effect will this have on your results?

You'll experience a grater deviation

Explanation:

You'll experience a greater deviation in your measurements, meaning your measures will have a bigger difference between them, and the greater these deviations the less accurate will be the measuring. This happens mainly because you're not replicating the measurement with the exact same conditions, in one of them you'll have an extra mass from the water.

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