Melting Point and Boiling Point of Organic Compounds
Social Alchemy
2nd Quarter / SY 2012 – 2013
Eng’r. Josephine A. Ng
CHM142L/B21
Concepcion, Jermin B.
Group# 2
Experiment No. 1
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MELTING POINT AND BOILING POINT OF ORGANIC COMPOUNDS
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ABSTRACT
The melting point (MP) and the boiling point (BP) are probably the most widely used physical constant in the field of science. Determining the boiling point and the melting point of a compound helps you to characterize an unknown solid in a quick, easy and cheap way. The temperature at which a compound turns from a solid state to a liquid state is known to be the melting point. On the contrary, the boiling point of a compound pertains to the temperature where the compound changes from liquid state to its gas state.
Many factors affect the boiling point and melting point of an organic compound, and one of which is the molecular structure. Purity and branching also affects the boiling and melting point of a compound. There are three trends that affect the boiling and melting points and these are the following: The relative strength of the four intermolecular attractions is factor significally affects the boiling point and the melting point of a compound. The overarching principle involved is simple: the strong the non-covalent interactions between molecules, the more energy are required, in the form of heat, to break them apart. The higher melting and boiling points signify the stronger non-covalent intermolecular forces. For molecules with a given functional group, boiling point increases as molecular weight increases. The key force acting here are Van der Waals dispersion forces, which boiling points and melting points are proportional to surface area. So as you increase the length of the chain, you also increase the surface area. And the increase also increases the ability of each individual molecule to attract each other. Lastly, the symmetry or lack thereof. Symmetry is
2nd Quarter / SY 2012 – 2013
Eng’r. Josephine A. Ng
CHM142L/B21
Concepcion, Jermin B.
Group# 2
Experiment No. 1
-------------------------------------------------
MELTING POINT AND BOILING POINT OF ORGANIC COMPOUNDS
-------------------------------------------------
ABSTRACT
The melting point (MP) and the boiling point (BP) are probably the most widely used physical constant in the field of science. Determining the boiling point and the melting point of a compound helps you to characterize an unknown solid in a quick, easy and cheap way. The temperature at which a compound turns from a solid state to a liquid state is known to be the melting point. On the contrary, the boiling point of a compound pertains to the temperature where the compound changes from liquid state to its gas state.
Many factors affect the boiling point and melting point of an organic compound, and one of which is the molecular structure. Purity and branching also affects the boiling and melting point of a compound. There are three trends that affect the boiling and melting points and these are the following: The relative strength of the four intermolecular attractions is factor significally affects the boiling point and the melting point of a compound. The overarching principle involved is simple: the strong the non-covalent interactions between molecules, the more energy are required, in the form of heat, to break them apart. The higher melting and boiling points signify the stronger non-covalent intermolecular forces. For molecules with a given functional group, boiling point increases as molecular weight increases. The key force acting here are Van der Waals dispersion forces, which boiling points and melting points are proportional to surface area. So as you increase the length of the chain, you also increase the surface area. And the increase also increases the ability of each individual molecule to attract each other. Lastly, the symmetry or lack thereof. Symmetry is