Question

List two nonmetal elements that combine with three hydrogen atoms to satisfy the octet rule.

Short answer

Nitrogen and phosphorus combine with three hydrogens to satisfy the octet rule.

Step-by-step solution

Identifying Nonmetals

First, we need to identify elements that are classified as nonmetals. Nonmetal elements include oxygen, sulfur, nitrogen, phosphorus, and the halogens among others.

Understanding the Octet Rule

The octet rule is a chemical rule of thumb that states that atoms tend to combine in such a way that they have eight electrons in their valence shell, achieving a stable electron configuration similar to that of the noble gases.

Determining Combinations with Hydrogen

Nonmetals that can combine with three hydrogen atoms (H) to satisfy the octet rule would typically have five valence electrons each. Combining with three hydrogens means that these nonmetals will share three electrons with hydrogen, effectively reaching the eight-electron (octet) configuration.

Choose Suitable Nonmetals

Nitrogen (N) and phosphorus (P) each have five valence electrons and can form a total of three covalent bonds with hydrogen atoms to complete their octet. Thus, they both can achieve a stable electron configuration following the octet rule.

Key concepts

Nonmetals

Nonmetals are elements that have distinct properties different from metals; they are typically poor conductors of heat and electricity. Unlike metals, nonmetals have lower melting and boiling points.
These elements are found primarily on the right side of the periodic table. They tend to have a high electronegativity, meaning they attract electrons more strongly than metals when forming compounds.

• Examples of nonmetals include oxygen, sulfur, nitrogen, and carbon.
• Many nonmetals exist in nature as gases or brittle solids.
• They play essential roles in various chemical and biological processes.

Understanding nonmetals is crucial in chemistry because they frequently engage in forming covalent bonds, which are vital for creating numerous compounds, including those important for life.

Covalent Bonds

Covalent bonds are a type of chemical bond where two atoms share one or more pairs of electrons. This sharing allows them to attain a more stable electron configuration.
Unlike ionic bonds, which involve the transfer of electrons, covalent bonds involve the actual sharing, which usually occurs between nonmetal atoms.

• Covalent bonds can be single, double, or triple, depending on the number of shared electron pairs.
• They are generally quite strong and require significant energy to break.
• The formation of covalent bonds leads to the creation of molecules.

In nature, covalent bonds are common in organic molecules, which include carbohydrates, proteins, and fats. These molecules and their bonds are critical to life because they make up the structures within cells and tissues.

Valence Electrons

Valence electrons are the outermost electrons of an atom and are crucial in determining how the atom will interact or bond with others. These electrons reside in the highest energy level and are the most involved in forming bonds.
Recognizing the number of valence electrons can help predict an element's reactivity and the type of bonds it will form.

• Elements with similar valence electron numbers are typically grouped together in the periodic table, as they share similar chemical properties.
• Nonmetals generally have more valence electrons compared to metals, which influences their ability to form covalent bonds.
• In general, reaching a full set of eight valence electrons, or an "octet," makes the atoms more stable.

Valence electrons play a crucial part in the chemical behavior of elements because they are responsible for the formation of chemical bonds that create various compounds.

Nitrogen and Phosphorus

Nitrogen and phosphorus are two key nonmetals with vital roles in both chemistry and biology.
Both elements have five valence electrons, enabling them to form up to three covalent bonds by sharing electrons with other elements, like hydrogen, to achieve a full octet.

• Nitrogen (N): Found in proteins, DNA, and the atmosphere. It typically forms a nitrogen triple bond, which is very strong.
• Phosphorus (P): Essential for life as it forms part of the backbone of DNA molecules and is involved in energy transfer through ATP (adenosine triphosphate).
• Both can combine with three hydrogen atoms, forming compounds like ammonia (NH₃) or phosphine (PH₃), effectively satisfying the octet rule.

Understanding these elements and their bonding behavior is essential in fields like biochemistry and environmental science, where they support crucial life processes.