ShmoopTube

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Here's your shmoop du jour...a la Bio.

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Which statement incorrectly describes the properties of water?

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And here are the potential answers...

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Water. H20. That stuff we're all supposed to drink 8 glasses of every day.

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Even those of us with a drinking problem.

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But aside from hydrating our body, it has some other really cool, unique properties

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that are good to know for the AP bio test. And since this is a "which statement incorrectly

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describes" question...

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...we can just look at every single answer choice to determine which one ain't doin'

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it for us. Starting with our first answer choice...is

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water a nonpolar molecule? Well, what does that mean? Does it just like

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the thermostat cranked up to 90? Nope... polarity in science refers to differences

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in charge or ELECTRONEGATIVITY between atoms in a molecule.

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Electronegativity means the tendency to attract electrons. With or without makeup.

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In this problem, it means that if our water molecule were to have a different electronegativity

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around oxygen compared to its two hydrogen atoms, the molecule would be polar.

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Hm ok...so we know that Oxygen is a super electronegative atom, and attracts lots of

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negative charge to it. It's something we should just know and memorize

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because it's one of those things that is just uber-important.

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Hydrogen, on the other hand, does not have a high electronegativity. Sorry, hydrogen.

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We're sure you make up for it by having a great personality.

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So even though there are two hydrogen atoms for one oxygen in every water molecule...

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...the water molecule is still super negative around the oxygen and is unbalanced in charge.

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This difference in charge makes water POLAR. So our answer is A.

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Now start chugging. You've still got 6 glasses to go today.

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