AP BIOLOGY

Detailed explanation-1: -A water molecule has three atoms: two hydrogen (H) atoms and one oxygen (O) atom. That’s why water is sometimes referred to as H2O. A single drop of water contains billions of water molecules.

Detailed explanation-2: -Two hydrogen atoms and two oxygen atoms together make hydrogen peroxide, which is less stable than water.

Detailed explanation-3: -The area around the oxygen is somewhat negative compared to the opposite, hydrogen-containing end of the molecule, which is slightly positive. Opposites attract, so this lopsided charge difference allows bonds to form between the hydrogen and oxygen atoms of adjacent H2O molecules.

Detailed explanation-4: -Answer and Explanation: Water is considered a pure substance because the oxygen and hydrogen within it are bonded together.

Detailed explanation-5: -Water is a simple molecule consisting of one oxygen atom bonded to two different hydrogen atoms. Because of the higher electronegativity of the oxygen atom, the bonds are polar covalent (polar bonds).