Chapter 2 Essay

Submitted By Czawacki
Words: 744
Pages: 3

Describe each of the following types of chemical bonds:
Nonpolar covalent bonds
Polar covalent bonds
Ionic bonds
Hydrogen bonds
Select one of those types of bonds and describe a biologically-important molecule that is made of this type of bond (what atoms are involved? what is the biological importance of the molecule?)

An important first step is to know what a chemical bond is. A chemical bond is just the attraction between atoms (the smallest unit of matter) which results in forming a chemical substance containing two or more atoms. Below you will see a brief description of the following chemical bonds: Nonpolar covalent bond, polar covalent bond, ionic bond, and hydrogen bond.
1.) Nonpolar covalent bond: Occurs between two atoms of the same element and the electrons are ultimately shared equally. This is due to both of the atoms having the same electronegativity. A great example of this bond is the single bond between two hydrogen molecules. Each hydrogen molecule has one electron thus they are sharing the electrons equally. Also it is important to know what the term covalent bond means. Summed up this occurs when two atoms are sharing electrons
2.) Polar covalent bond: Occurs when sharing of electrons is not equal. So one atom binds more strongly to an electronegative atom. A good example of a polar covalent bond is the bonds between the oxygen and hydrogen atoms of a water molecule. The hydrogen and oxygen molecules have different polarity. Hydrogen has one electron to oxygen’s eight thus the sharing of electrons is unequal and since oxygen has more electrons it is considered the more negative molecule
3.) Ionic bond: This type of bonding occurs when the transfer of electrons between atoms takes place. This all results in two oppositely charged ions. Generally in ionic bonds a metal will lose electrons to become a positively charged cation. On the other hand a nonmetal accepts electrons becoming negatively charged anion. It is important to remember that an ionic bond requires an electron donor which is often a metal, and it also requires an electron acceptor being a nonmetal. A good example of an ionic bond takes place between chloride and sodium. Sodium has eleven electrons with a single electron in its third electron shell. Chlorine on the other hand has seventeen electrons with seven electrons in its valence shell. When a chlorine and sodium atom come together the electron in the third shell of sodium is transferred to chlorine. Both of the sodium and chlorine atoms end up with completed valence shells. This electron transfer moves one negative charge from sodium to the chlorine. Sodium ends up with eleven protons and ten electrons with a net overall charge of +1. The chlorine molecule which has gained an electron now has seventeen protons and eighteen electrons resulting in an overall net charge of -1. Since these two molecules now have opposite charges they end up…