AP BIOLOGY

Detailed explanation-1: -The oxygen atom has an electronegativity value of 3.5 while that of the hydrogen atom is 2.1. Oxygen has higher electronegativity so it attained slight negative charge while hydrogen atoms attain slight positive charge. Therefore, a molecule of water due to these charges is a polar molecule.

Detailed explanation-2: -The oxygen atom contains 6 outer electrons, but atoms are only stable when there are 8 outer electrons. As a result, oxygen atoms seek out other atoms that can share electrons. This imbalance of outer electrons means an oxygen atom has a slight negative charge (-2) because of the missing 2 electrons.

Detailed explanation-3: -In a water molecule (H2O), the oxygen nucleus with +8 charges attracts electrons better than the hydrogen nucleus with its +1 charge. Hence, the oxygen atom is partially negatively charged and the hydrogen atom is partially positively charged.

Detailed explanation-4: -Answer and Explanation: Oxygen has a partial negative charge because it has a polar covalent bond with hydrogen. In the water molecule, one oxygen atom is bound to two hydrogen atoms.