How atoms bond - George Zaidan and Charles Morton

TED-Ed

15 Oct 201303:34

Summary

TLDRThis script explores the fascinating world of atomic bonding. It explains how atoms form ionic bonds by transferring electrons, as seen in table salt, and covalent bonds by sharing electrons, crucial for proteins and DNA. The arrangement of electrons, particularly those in the outermost orbitals, dictates an atom's bonding potential. The script highlights the importance of chemical bonds in creating molecules, from simple oxygen molecules to the complex structure of human chromosomes.

Takeaways

🔬 Atoms typically bond with other atoms to form compounds, rather than existing alone.
🤝 Bonds can be formed between atoms of the same element or different elements.
🌐 In ionic bonding, one atom transfers one or more electrons to another, resulting in charged ions that are attracted to each other.
🧂 Table salt (sodium chloride) is an example of a compound held together by ionic bonds.
🔗 Covalent bonds occur when atoms share electrons rather than transferring them, creating a mutual attraction between the atoms.
🧬 Proteins and DNA in our bodies are largely held together by covalent bonds.
🌐 The number of atoms an atom can bond with is determined by the arrangement of its electrons.
💡 Only the outermost electrons, which have the most energy, participate in bonding.
🔑 Carbon, nitrogen, and oxygen tend to form four, three, and two bonds respectively, due to the number of valence electrons they have.
🌌 Molecules are groups of atoms that share electrons covalently and can range from small, like oxygen gas, to extremely large, like human chromosomes.

Q & A

How do atoms typically form bonds?
-Atoms typically form bonds by either sharing or transferring electrons. This can occur between atoms of the same element or different elements.
What is an ionic bond and how is it formed?
-An ionic bond is formed when one atom completely overwhelms another, resulting in the transfer of one or more electrons from one atom to another, creating a positively charged ion and a negatively charged ion. The attraction between these opposite charges is called an ionic bond.
What is an example of a substance held together by ionic bonds?
-Table salt, or sodium chloride, is an example of a substance held together by ionic bonds, where each sodium atom gives up an electron to each chlorine atom.
How do the ions in sodium chloride arrange themselves?
-The ions in sodium chloride arrange themselves in a 3D grid called a lattice, where each sodium ion is bonded to six chloride ions and each chloride ion is bonded to six sodium ions.
What is a covalent bond and how does it differ from an ionic bond?
-A covalent bond is formed when atoms share electrons rather than transferring them. This is different from an ionic bond, where electrons are transferred from one atom to another.
Which biological molecules in our bodies are held together by covalent bonds?
-Proteins and DNA in our bodies are largely held together by covalent bonds.
How does the arrangement of electrons determine the number of bonds an atom can form?
-The number of bonds an atom can form is determined by the arrangement of its outermost electrons, which are the ones available for bonding.
What is the role of the outermost electrons in bonding?
-The outermost electrons, being the ones with the most energy, are the only electrons that participate in bonding, whether it's ionic or covalent.
Why does hydrogen typically form only one bond?
-Hydrogen typically forms only one bond because it has only one electron available for bonding.
What are molecules and how are they formed?
-Molecules are groups of atoms that share electrons covalently with each other. They can range from small, like oxygen gas which consists of two oxygen atoms, to very large, like human chromosome 13 which is made up of two molecules with over 37 billion atoms each.
What holds the structure of a molecule together?
-The structure of a molecule is held together by chemical bonds, which can be either ionic or covalent, depending on the type of bonding between the atoms.

Outlines

00:00

🔬 Chemistry of Bonding

This paragraph explains the concept of chemical bonding between atoms. It discusses how atoms can form bonds with either the same or different elements, leading to the formation of ions and ionic bonds. The example of sodium chloride is used to illustrate how ionic bonds work, with sodium atoms giving up an electron to chlorine atoms, resulting in a 3D lattice structure. The paragraph then contrasts this with covalent bonding, where electrons are shared rather than transferred, using proteins and DNA as examples. The discussion also covers the role of valence electrons in bonding, and how the number of bonds an atom can form is determined by the arrangement of these outermost electrons. The paragraph concludes by mentioning that groups of atoms sharing electrons are known as molecules, which can range from small, like oxygen gas, to extremely large, like human chromosomes.

Mindmap

Keywords

💡Ionic Bond

An ionic bond is a type of chemical bond formed through the electrostatic attraction between oppositely charged ions. In the video, it is mentioned as the kind of bond where one atom completely overwhelms another, resulting in the transfer of electrons and the formation of ions. An example given is table salt (sodium chloride), where each sodium atom gives up an electron to a chlorine atom, creating a positively charged sodium ion and a negatively charged chloride ion. These ions then arrange in a 3D lattice, forming an ionic bond.

💡Covalent Bond

A covalent bond is a chemical bond formed by the sharing of electron pairs between atoms. The video likens this to a potluck where each party contributes something and shares with the other. Covalent bonds are prevalent in complex molecules like proteins and DNA, where atoms share electrons to achieve a stable electron configuration. The number of atoms with which an atom can form covalent bonds depends on the arrangement of its electrons.

💡Electrons

Electrons are negatively charged subatomic particles that orbit the nucleus of an atom. They play a crucial role in chemical bonding, with only the valence electrons (those in the outermost orbitals) participating in bonding. The video explains that in both ionic and covalent bonds, it is the outermost electrons that are involved in the bonding process, such as the electron transfer from sodium to chlorine in the formation of sodium chloride.

💡Molecules

Molecules are groups of atoms that are bonded together by chemical bonds and represent the smallest fundamental unit of a chemical compound that can take part in a chemical reaction. The video uses molecules to illustrate how covalent bonds form complex structures, ranging from simple diatomic molecules like oxygen gas (O2) to the enormous molecules found in human chromosomes, each containing billions of atoms.

💡Valence Electrons

Valence electrons are the electrons found in the outermost electron shell of an atom and are the ones involved in chemical bonding. The video emphasizes that only these electrons, which have the most energy and are furthest from the nucleus, participate in bonding. The number of valence electrons determines how many bonds an atom can form, as seen with carbon forming four bonds, nitrogen three, and oxygen two.

💡Nuclear Charge

Nuclear charge refers to the positive charge of an atomic nucleus, which is determined by the number of protons it contains. The video explains that atoms are electrically neutral because the number of protons in the nucleus is balanced by the number of electrons orbiting the nucleus. This balance is crucial for understanding how atoms interact and form bonds.

💡Orbitals

Orbitals are regions around the nucleus of an atom where electrons are likely to be found. The video mentions that not all electrons are available for bonding, but only those in the outermost orbitals, which are the ones with the most energy. These orbitals are critical for understanding how electrons are arranged and how they participate in chemical bonding.

💡Lattice

A lattice is a regular, repeating arrangement of particles in a crystal. In the context of the video, the ionic lattice is used to describe the three-dimensional grid formed by the ions in a crystal of sodium chloride. Each ion is bonded to others in a specific geometric arrangement, creating a stable, repeating structure that characterizes the crystal.

💡Proteins

Proteins are large biomolecules composed of amino acids and are essential for the structure, function, and regulation of the body's cells, tissues, and organs. The video highlights that proteins, along with DNA, are held together by covalent bonds, which are crucial for their complex three-dimensional structures and biological functions.

💡Chromosomes

Chromosomes are structures within cells that contain genetic information in the form of DNA. The video uses human chromosome 13 as an example to illustrate the vast scale of molecules, noting that it consists of just two molecules but contains over 37 billion atoms. This example underscores the complexity and scale at which chemical bonds organize matter at the molecular level.

Highlights

Atoms typically bond with other atoms rather than existing alone.

Bonds can form between atoms of the same or different elements.

Ionic bonds result from the transfer of electrons, creating charged ions that attract each other.

Sodium chloride (table salt) is an example of a substance held together by ionic bonds.

In ionic bonds, electrons are transferred permanently, unlike covalent bonds where electrons are shared.

Covalent bonds involve the sharing of electrons between atoms.

Proteins and DNA in our bodies are largely held together by covalent bonds.

The number of atoms an atom can covalently bond with depends on its electron arrangement.

Electrons in the outermost orbitals, furthest from the nucleus, are the ones that participate in bonding.

Atoms of pure, unbonded elements are electrically neutral with equal numbers of protons and electrons.

Carbon, nitrogen, and oxygen tend to form four, three, and two bonds respectively due to their electron configurations.

Hydrogen, with only one electron, can form only one bond.

Atoms can form more bonds than expected in special cases, but this is not typical.

Molecules are groups of atoms that share electrons covalently.

Molecules can range from small, like oxygen gas, to extremely large, like human chromosome 13.

Chemical bonds are the fundamental force that holds atoms together in molecules.