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Organic Chemistry - Hydrogen Bonding

Hydrogen is not very electronegative. So when it gets involved in a bond, it does not take the electrons it is sharing with some other atom. Therefore, the other atom gets to take the electron. The other atom, therefore, tends to be partially negative and the hydrogen atom tends to be partially positive. The hydrogen oxygen bond is polar for the reason we just talked about. 

The bond between the positive hydrogens of one molecule and the negative oxygens of another is called a hydrogen bond. Here is what hydrogen bonding is, in a molecule that has hydrogen bonded to oxygen, the hydrogen is positive and the oxygen is negative. When a bunch of those molecules get together, a link is formed between the positive hydrogen of one molecule and the negative oxygen of the next. We called that link a hydrogen bond. 

If a substance has an OH group and undergoes hydrogen bonding it means two things. One, the substance will have a higher boiling point because the hydrogen bonds tend to hold the molecules together. And two, the substance will be more soluble in water because the hydrogen bonds between the substance and water tend to help the substance mix well with water.