AP BIOLOGY

Detailed explanation-1: -Atoms join together to form molecules. 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.

Detailed explanation-2: -The hydrogen atom is the simplest of all atoms: it consists of a single proton and a single electron. In addition to the most common form of the hydrogen atom that is called protium, two other isotopes of hydrogen exist: deuterium and tritium.

Detailed explanation-3: -An atom is the smallest particle of an element, like oxygen or hydrogen. Atoms join together to form molecules. A water molecule has three atoms: 2 hydrogen (H) atoms and 1 oxygen (O) atom. That’s why water is sometimes referred to as H2O.

Detailed explanation-4: -Answer. The strength by which an atom attracts the pair of electrons used to form a chemical bond is measured by electronegativity. Since oxygen has a higher electronegativity value than hydrogen, the electrons that form covalent bonds are drawn closer to the oxygen atom and away from the two hydrogen atoms.

Detailed explanation-5: -Hydrogen bonds are attractions of electrostatic force caused by the difference in charge between slightly positive hydrogen ions and other, slightly negative ions. In the case of water, hydrogen bonds form between neighboring hydrogen and oxygen atoms of adjacent water molecules.