When studying subsitution and elimination reactions you will often have to analyze between the solvents used in the reaction to help determine the rate and mechanism that will take place. In this article I will help you differentiate between Polar Protic and Polar Aprotic solvents
A polar solvent, as the name implies, has 2 poles. A partially positive and a partially negative pole. This occurs when the solvent molecule is made up of atoms that while covalently bound, are not sharing the electrons equally among the bonding atoms. The more electronegative atom will pull the electrons towards itself resulting in a slightly negative charge or 'pole', while the less electronegative atom winds up with a partially positive charge or 'pole'
The word protic, in polar protic solvents, comes from the word proton, which is simply the positive nucleus of a hydrogen atom. When hydrogen is bound to a very electronegative atoms like N, O or F, these atoms form polar covalent bonds that are so extreme, to the point where not only is hydrogen partially positive, but its entire nucleus is exposed. Since the nucleus of hydrogen contains one proton, the exposed proton makes the solvent protic. If another highly electronegative atom like N, O or F comes across this protic hydrogen, it will attempt to make a bond, called a hydrogen bond. Examples of polar protic solvents include water and ammonia
Polar aprotic solvents tend to be the most confusing. While the solvent molecules do have partial charges or polarity, they are incapable of hydrogen bonding. this is because the polarity typically does not occur between a hydrogen and nitrogen, or hydrogen and oxygen atom.
If a negative ion is dissolved in this solution it will not find itself surrounded by partially positive stabilizing hydrogen atoms. This is the exact opposite of what occurs when a partially negative ion is dissolved in a polar protic solvent.
A polar solvent, as the name implies, has 2 poles. A partially positive and a partially negative pole. This occurs when the solvent molecule is made up of atoms that while covalently bound, are not sharing the electrons equally among the bonding atoms. The more electronegative atom will pull the electrons towards itself resulting in a slightly negative charge or 'pole', while the less electronegative atom winds up with a partially positive charge or 'pole'
The word protic, in polar protic solvents, comes from the word proton, which is simply the positive nucleus of a hydrogen atom. When hydrogen is bound to a very electronegative atoms like N, O or F, these atoms form polar covalent bonds that are so extreme, to the point where not only is hydrogen partially positive, but its entire nucleus is exposed. Since the nucleus of hydrogen contains one proton, the exposed proton makes the solvent protic. If another highly electronegative atom like N, O or F comes across this protic hydrogen, it will attempt to make a bond, called a hydrogen bond. Examples of polar protic solvents include water and ammonia
Polar aprotic solvents tend to be the most confusing. While the solvent molecules do have partial charges or polarity, they are incapable of hydrogen bonding. this is because the polarity typically does not occur between a hydrogen and nitrogen, or hydrogen and oxygen atom.
If a negative ion is dissolved in this solution it will not find itself surrounded by partially positive stabilizing hydrogen atoms. This is the exact opposite of what occurs when a partially negative ion is dissolved in a polar protic solvent.
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Learn more about these organic solvents by watching my youtube tutorial video on this topics
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