which exhibits hydrogen bonding (there can be more than 1)

1. IF7
2. SiH4
3. CH3CH2OH
4. (CH3)2CHOH
5. PCl3
6. CH3CHCHCH3

* do you have any tips for figuring it out?

H bonding, by definition, takes place with H of one molecule and a highly electronegative atom (usually O, N, F) of another molecule. With that in mind, 1, 2, 5, and 6 are eliminated. That leave 3 and 4 to show H bonding. And alcohols have and O of one molecule and and H of another molecule of the same material.

To determine which molecules exhibit hydrogen bonding, you can follow these steps:

1. Identify the presence of hydrogen (H) atoms in each molecule.

2. Look for highly electronegative atoms like oxygen (O), nitrogen (N), and fluorine (F) that are directly bonded to the hydrogen atoms in the molecule.

3. Check whether these electronegative atoms form hydrogen bonds with other molecules.

Now, let's analyze the given molecules:

1. IF7: This compound does not have any hydrogen atoms bonded to electronegative atoms, so it does not exhibit hydrogen bonding.

2. SiH4: Similar to the previous compound, there are no hydrogen atoms bonded to electronegative atoms, so it does not exhibit hydrogen bonding either.

3. CH3CH2OH: This molecule contains an oxygen atom (O) bonded to a hydrogen atom (H). Oxygen is highly electronegative, and it can form hydrogen bonds with other molecules. Therefore, CH3CH2OH exhibits hydrogen bonding.

4. (CH3)2CHOH: Like the previous molecule, (CH3)2CHOH also contains an oxygen atom (O) bonded to a hydrogen atom (H), allowing it to form hydrogen bonds with other molecules. Thus, (CH3)2CHOH exhibits hydrogen bonding.

5. PCl3: This compound, being composed of phosphorus (P) and chlorine (Cl), lacks any hydrogen atoms bonded to highly electronegative atoms. Hence, it does not exhibit hydrogen bonding.

6. CH3CHCHCH3: Similar to the previous compounds, there are no hydrogen atoms bonded to highly electronegative atoms, so it does not exhibit hydrogen bonding.

Based on the analysis, the molecules that exhibit hydrogen bonding from the given options are:

- CH3CH2OH (Option 3)
- (CH3)2CHOH (Option 4)