Estimate # Water Molecules in 1.5mm Raindrop

Thread starter mh922253
Start date Sep 13, 2005

AI Thread Summary

To estimate the number of water molecules in a 1.5 mm raindrop, first calculate the volume using the formula for the volume of a sphere, which is approximately 14.1 mm³. Given that there is 1 gram of water per milliliter, this volume translates to about 0.0141 grams of water. Since 18 grams corresponds to one mole of water, this means the raindrop contains roughly 0.000783 moles of water. Multiplying by Avogadro's number (approximately 6.022 x 10²³) results in an estimate of about 4.7 x 10²⁰ water molecules in the raindrop. This calculation highlights the vast number of molecules present even in a small volume of water.

Sep 13, 2005

mh922253

Hi everyone i have a physics question... the question is:
Estimate the number of water molecules in a raindrop 1.5 mm in radius.
i really dont...
WHAT IS THE MOLAR VOLUME OF WATER?

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Sep 13, 2005

LeonhardEuler

Gold Member

There is one gram in a mililiter of water and 18 grams in a mole of water, so I'd say there is one eighteenth of a mole of water in a milileter of water.

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