chemical bonding almost everything we see or touch in our daily life is the result of a chemical bond the air we breathe the food we eat the clothes we wear and so on are all made up of one or more chemical bonds the world is generally not composed of isolated atoms rather it is composed of molecules formed as a result of chemical bonds the strong force that holds together the constituent particles atoms ions or molecules in a chemical species is known as chemical bond the chemical bonds are broadly classified as ionic bond [Music] and covalent
bond let us discuss these chemical bonds in detail in this module the bonding which results due to the complete transfer of valence electrons between atoms is called ionic bonding it is a type of chemical bond that generates two oppositely charged ions ionic bonding is observed because metals have few leptons in its outermost orbital by losing those electrons these metals can achieve noble gas configuration and satisfy the octet rule similarly nonmetals that have close to eight electrons in its valence shell tend to readily accept electrons to achieve its noble gas configuration in ionic bonding more than
one electron can be donated or received to satisfy the octet rule sodium metal has electronic configuration as two eight and one it has one electron more than a stable noble gas structure if it gives away that electron it would become more stable on the other side chlorine has electronic configuration as two eight and seven it has one electron short of a stable noble gas structure if it could gain an electron it too would become more stable thus the sodium atom donates its valence electron to achieve stable octet configuration this creates a positively charged cation due
to the loss of electron the chlorine atom receives one electron to achieve its stable octet configuration this creates a negatively charged anion due to the addition of one electron the sodium ions and chloride ions are held together by their strong electronic attractions between the positive and negative charges covalent bonding a covalent chemical bond results from the sharing of electrons between two atoms with similar electronegativities the electronic configuration of chlorine atom is one electron short of the argon configuration the formation of the chlorine molecule can be understood in terms of the sharing of a pair of
electrons between the two chlorine atoms each chlorine atom contributing one electron to the shared pair in the process both chlorine atoms attain the outer shell octet of the nearest noble gas that is our connect the dots represent electrons such structures are referred to as Lewis dot structures thus the chlorine atoms are joined by a single covalent bond a single covalent bond is formed when one pair of electrons are shared between two atoms it is depicted by a single line between the two atoms a double bond is formed when two atoms share two pairs of electrons
with each other it is depicted by two horizontal lines between two atoms in a molecule this type of bond is much stronger than a single bond but less stable this is due to its great amount of reactivity compared to a single bond for example in the carbon dioxide molecule we have two double bonds between the carbon and oxygen atoms when three pairs of electrons are shared between two atoms in a molecule a triple bond is formed it is the least stable out of the three general types of covalent bonds the two carbon atoms in the
ethane molecule are joined by a triple bond
