How Many Water Molecules Are in a 1.5 mm Raindrop?

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To estimate the number of water molecules in a 1.5 mm radius raindrop, first calculate the volume using the formula V=4/3πr^3, treating the raindrop as a sphere. The density of water is 1 gram per cubic centimeter, which allows for mass calculation from the volume. Then, convert mass to moles using the molecular mass of water, approximately 18 grams per mole. Finally, multiply the number of moles by Avogadro's number, about 6.02 x 10^23, to find the total number of molecules. This method provides a clear approach to solving the problem.
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am i in the right place?

i everyone i have a physics question but i am not sure if i am in the right place or not... the question is:
Estimate the number of water molecules in a raindrop 1.5 mm in radius.
i really don't want you to solve it just give me the equation that i am supposed to use to solve the question...

and again... if i am in the wrong place...please tell me where i am supposed to post this question

thanks a lot
 
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This is better posted in the homework forum.

Look up the molar volume of water. You'll find out how many atoms fit into a given volume. The rest is just volumetric calculation.
 
The density of water is 1 gram per cubic centimeter. The molecular mass of water is about 18 grams per mole. there are about 6.02*10^23 molecules in a mole. Assuming the raindrop is spherical, you can find its volume from V=\frac{4}{3}\pi r^3. Using the desnity, you can find the mass, using the mass you can find the # of moles, using the # of moles you can find the # of molecules.
 
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