Chemical Compounds Inorganic Compounds Organic Compounds

Inorganic compounds are those that derived from nonliving systems, such as minerals and gases. Organic compounds are those that derived from living systems, for example, plants and animals. The term valence describes the number of bonds usually formed by each element. For example, carbon generally forms four bonds and is therefore said to be tetravalent. Nitrogen generally forms three bonds and is therefore trivalent. Oxygen forms two bonds and is divalent, while hydrogen and the halogens form one bond and are monovalent.

Monovalent Divalent Trivalent Tetravalent

Representing atomic arrangement in organic molecule: Representing atom arrangement in organic molecules is of vital importance. This is due to the fact that the location of the bonds that connect atoms in organic molecules affects the reactivity and in general the chemical and physical properties.

Boiling point=-23 C Boiling Point=78.4 C

Polarity of organic compounds The difference in electronegativity between O and Na is so great that both electrons of the bond are possessed solely by the oxygen atom, rendering the oxygen negatively charged and the sodium positively charged. The bond between the oxygen and sodium, called an ionic bond, is the result of the force of attraction between the two oppositely charged ions.

Covalent Polar Covalent Ionic Small difference in electronegativity Large difference in electronegativity

Types of Organic Chemical Reactions 1. Oxidation-Reduction Reactions 2. Addition-Elimination Reactions 3. Substitution Reactions 4. Pericyclic Reactions 5. Rearrangement Reactions 6. Photochemical Reactions 7. Free radical Reactions

Hydrocarbons Hydrocarbons are compounds comprised of just C and H; for example: Ethane Ethylene Acetylene Benzene

Constitutional Isomers Isomers are compounds that are constructed from the same atoms (same molecular formula) but that still differ from each other. Isomers Stereoisomers Constitutional Isomers

Constitutional Isomers Same molecular formula but different constitution (order of connectivity of atoms) Stereoisomer: Compounds that differ from each other only in the three-dimensional, spatial arrangement of their atoms, but not in the connectivity of their atoms. Cis and Trans Isomer The term cis is used to signify that the two groups are on the same side, while the term trans signifies that the two groups are opposite sides, for example

We begin our exploration of the various kinds of stereoisomers by investigating the relationship between an object and its mirror image. Chirality or chiral center Chiral center is a carbon atom that bonds with four different groups: Note/ All three-dimensional objects can be classified as either chiral or achiral.

Enantiomers When a compound is chiral, it will have one nonsuperimposable mirror image, called its enantiomer.

Diastereomers Diastereomers are stereoisomers that are not mirror images of each other. Note/ Diastereomers are different in physical properties whereas Enantiomers are different in chemical reactivity.

Acidity and Basicity: A. Arrhenius theory According to this theory acids are those substances that donate hydrogen ion while bases are those that donate hydroxyl ion. B. Brønsted–Lowry acid–base theory This theory states that acids donate proton whereas bases accept proton C. Lewis theory According to this theory acids can be defined as those that has empty orbitals while bases can be defined as those that has pair of electron that ready for donation

Mechanism of Reactions Mechanism of reactions comprises all steps that a chemical reaction can proceed (or detail of a chemical reaction). Organic Reactions: Oxidation Reduction Reaction (Redox) In this kind of organic reaction transfer of electron is not only factor of Redox but also addition and elimination of hydrogen is reduction and oxidation, respectively

Figure 1 shows the structure of L-ascorbic acid (left) and dehydro-L-ascorbic acid (right)

2. Substitution Reactions In this reaction, a group (a Substituent) in an organic compound can be replaced by another one in a certain condition.

3. Addition and Elimination Reactions This type of organic reaction involves a group that can be added onto an organic compound whereas elimination reactions are reverse of it.