3. why is water considered to be a polar covalent molecule?

A polar molecule simply means the charges are uneven throughout the molecule. Some parts are slightly negative (outside the oxygen), and some parts are slightly positive (outside the hydrogen atoms). A covalent bond happens when atoms share their electrons with each other. So, polar covalent just means that the atoms aren't sharing their electrons evenly, creating slight charges in the molecule. Water is polar covalent because the highly electronegative oxygen atom pulls electrons to it, making the region around the oxygen more negative than the areas around the two hydrogen atoms.

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