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How Many Molecules? Stoichiometry Lab

We tested our new found stoichiometry skills by figuring out how many molecules we would consume if we drank from the school water fountain for 30 seconds.

How Many Molecules? Stoichiometry Lab

I had my students make predictions before we started.  Their predictions turned out to be waaaaaaaaaaaaaaaaayyyyyyyy off.  Let’s just say the highest prediction was 1,000,000 molecules of water.

Filling Water Pitcher at Drinking Fountain

Each group collected 30 seconds of water from the water fountain.  We measured the mass of water in each pitcher and averaged the results.

Water pitcher on scale

It turns out the size of a molecule is super tiny and super hard to wrap our minds around!