Term
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Definition
| weaker than covalent but still important. examples: electrostatic interactions, hydrogen bonds, van der Waals, hydrophobic interactions |
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Term
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Definition
| sharing of a pair of electrons(single bond) or multiple pairs (double/triple bonds). very strong: much energy must be expended to break. |
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Term
| electrostatic interactions |
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Definition
| a charged group on one molecule attracts opposite charge on another. E = kq1q2/Dr^2 (Coulombs' Law) D is dielectric constant. attraction is negative energy |
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Term
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Definition
| type of electrostatic interaction. hydrogen atom is shared by two electronegative atoms such as N,O. donor has tighter link than acceptor. H bonds are weaker and longer than covalent. |
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Term
| van der Waals interactions |
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Definition
| distribution of charge around an atom fluctuates over time. transient assymetry forces opposite assymetry in surrounding atoms. this causes attraction up to contact distance where electron clouds overlap and repulsion happens. |
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Term
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Definition
| polar: bent, not linear. highly cohesive. networks of H bonds hold structure together. versatile solvent. |
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Term
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Definition
| nonpolar molecules prefer to interact with each other rather than water; they have this tendency more in water than in other less polar and self associating solvents. |
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Term
| first law of thermodynamics |
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Definition
| the total energy of a system and its surroundings is constant. energy can not be created or destroyed |
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Term
| second law of thermodynamics |
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Definition
| total entropy of a system plus surroundings always increases. |
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Term
| pH formula (Henderson-Hasselbach eqn) |
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Definition
| pH = pKa + log([A-]/[HA]) |
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