Thermodynamics and Organic chemistry

 Thermodynamics and Organic chemistry

Thermodynamics means flow of heat and is derived from the  Greek` Thermo means heat and dynamics means flow, In our daily life,  useful reactions such as burning of fuel to produce heat energy, metabolic reactions to produce the necessary energy for biological functions, flow of electrons through circuit to produce electrical energy and so on. Thermodynamics, the study of the transformation of energy. 

First Law of thermodynamics

The law stated that  the net energy change of a closed system is equal to the heat transferred to the system minus the work done by the system.

System and Surrounding

The laws of thermodynamics and their applications,

An important part of the study of thermodynamics is a few terms and definitions which must be understood distincly .

System:

The part of the universe in which is under thermodynamic study and the rest of the universe is called as surroundings.

Surrounding:

Everything in the universe that is not the part of the system is called as surroundings.

Boundary:

It is defined as the imaginary or real surface separating the system from the surroundings is called as boundary.

Types of systems:

There are three types of thermodynamic systems depends on the nature of the boundary.

 Isolated System

The boundary is both folded and insulated, no interaction is possible with the surroundings. consequently, an isolated system is one that can transfer neither matter nor energy to and from its surroundings.

Example: A contained in a thermos flask, say boiling water, substance,  is another example of an isolated system.

Closed system

the boundary is folded but not insulated. consequently, a closed system is one which cannot transfer matter but can transfer energy in the form of heat, work and radiation to and from its surroundings

Example: A gas contained in a cylinder fitted with a piston conformation a closed system. As the piston is raised, the gas expands and transfers heat  in the form of work to the surroundings.

Open system

In the system ,the boundary is open and un-insulated. Therefore, an open system is one which can be transfer both matter and energy to and from its surroundings.

Intensive Properties

 A property is that does not depend on the quantity of matters present in the system is said to be Intensive Property.

 Extensive Properties

 A property is that does depend on the quantity of matters present in the system is said to be Extensive Property.

Molar heat capacity

if the system is defined as the amount of heat required to raise in temperature of 1 mole of the substance by 1 K.

Joule-Thomson Coefficient

The no of degrees temperature change produced per atmosphere drop in pressure under constant enthalpy conditions on passing a gas through the porous plug, is said to be Joule-Thomson coefficient.

Organic chemistry

                            Organic chemistry is a study of carbon compound . Carbon has a tendency to form more compounds with itself and other atoms (H-Hydrogen, O-Oxygen, N-Nitrogen, S-Sulphur and X-Halogens) than any other elements. The tendency of an atom to forms a self-linking of bonds with the atoms of the same element is said to be catenation. The high strength of C-C bond is manage for its catenation property. The word 'organic' means living organisms. Organic compounds are found only in the living organs. The basic unit of cell to living things, creates, consumes, and consists of mainly organic compounds. the genetic material, thelipid, DNA,  that forms our cell membrane and the glycogen the energy reserve stored in the liver are all organic compounds. Except few inorganic compounds like that salt, water etc... all others such as food,  fuel, clothing, cosmetics, medicine etc are compounds of carbon. All the essential biochemical reactions are also organic in nature leading to the fomation various essential bio-organic molecules such as lipoprotein, phospolipid, glycolipid.

                Synthesis of methane by Berthlot, acetic acid by Kolbe confirmed that organic compounds can be synthesized in laboratory. Since that millions of organic compounds are synthesised and characterised. The field of organic chemistry is very vast and its principles find applications in many industries including food, textile, pertrochemical, dye, polymers, pharmaceutical, cosmetics, fetilizers etc... Discuss the importance of organic chemistry is just like that describe a drop of water in a mighty ocean. chemical bonding and molecular structure will help in understanding the properties of organic compounds. the carbon has 4 valence electrons and its ground state of electronic configuration is 1s2 2s2 2p2. An atom can attain noble gas electronic configuration either by sharing of electrons or transferring. It is not possible for the carbon to form either C4^-    or C4⁺ ions to attain the nearest to the noble gas configuration. it requires large amount of energy. This implies that carbon cannot forms ionic bond. In all compounds of carbon contains 4 covalent bonds.

                         The formation of 4 covalent  bonds can be explained as below. During the bond formation, one of the electrons from 2s orbital is promoted to  the 2pz orbitals. The formation of 4 σ bonds by carbon can be explained on the basis of SP³ hybridisation of carbon. Carbon forms multiple ( = and ≡ ) bonds in certain compounds. These are explained by sp2 and sp hybridisation of carbon. The carbon forms relatively short bonds which enable the lateral overlap of unhybrid 2p orbitals of sp2 and sp hybrid carbon to form 1 and 2 pi bonds respectively. Molecular stucture can be derived from the type of hybridisation. An sp3 hybridised carbon will have a tetrahedral geometrical shape a sp2 hybridised carbon will have trigonal planar geometrical shape. and sp hybridised carbon will have a linear geometrical shape