Why is Water Less Dense than Ethanol?

markosheehan · Apr 18, 2017

Why is ethanol less dense than water if ethanol has a larger molecular weight. I think i heard it's something to do with water molecules being closer to each other. Why is this?

I like Serena · Apr 18, 2017

markosheehan said:

Why is ethanol less dense than water if ethanol has a larger molecular weight. I think i heard it's something to do with water molecules being closer to each other. Why is this?

Water has a polar molecular structure.
That is, the H-O-H atoms make an angle, causing a so called dipole moment, being negatively charged on one end, and positively charged on the other end.
Consequently $H_2O$ molecules have a stronger attraction to each other, and also to other polar molecules.

markosheehan · Apr 20, 2017

I like Serena said:

Water has a polar molecular structure.
That is, the H-O-H atoms make an angle, causing a so called dipole moment, being negatively charged on one end, and positively charged on the other end.
Consequently $H_2O$ molecules have a stronger attraction to each other, and also to other polar molecules.

Thanks

Why is Water Less Dense than Ethanol?

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Why is Water Less Dense than Ethanol?

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