Question

for each compound in the table below, decide whether there would be any hydrogen - bonding force between molecules of the compound, or between molecules of the compound and molecules of water.
compound hydrogen - bonding force
name formula or lewis structure between molecules of the compound? between molecules of the compound and molecules of water?
methylamine $h - c - \overset{h}{\underset{h}{n}} - h$ yes no yes no
hypobromous acid $hbro$ yes no yes no
methanimine $h - c = \overset{h}{\underset{\cdot \cdot }{n}} - h$ yes no yes no

Explanation:

To determine hydrogen - bonding, we use the rule: A hydrogen bond occurs when a hydrogen atom is bonded to a highly electronegative atom (N, O, F) and is in close proximity to another electronegative atom with a lone pair of electrons.

Methylamine ($\ce{CH3NH2}$)

• Between molecules of the compound: The structure has $\ce{N - H}$ bonds. The N atom is electronegative, and the H atom in $\ce{N - H}$ can form a hydrogen bond with the lone pair on N of another methylamine molecule. So, the answer is "yes".
• Between the compound and water: Water has $\ce{O - H}$ bonds. The H in $\ce{N - H}$ of methylamine can form a hydrogen bond with the lone pair on O of water, and the H in $\ce{O - H}$ of water can form a hydrogen bond with the lone pair on N of methylamine. So, the answer is "yes".

Hypobromous acid ($\ce{HBrO}$)

• Between molecules of the compound: The structure has $\ce{O - H}$ bonds. The O atom is electronegative, and the H atom in $\ce{O - H}$ can form a hydrogen bond with the lone pair on O of another $\ce{HBrO}$ molecule. So, the answer is "yes".
• Between the compound and water: Water has $\ce{O - H}$ bonds. The H in $\ce{O - H}$ of $\ce{HBrO}$ can form a hydrogen bond with the lone pair on O of water, and the H in $\ce{O - H}$ of water can form a hydrogen bond with the lone pair on O of $\ce{HBrO}$. So, the answer is "yes".

Methanimine ($\ce{H2C = NH}$)

• Between molecules of the compound: The molecule has $\ce{N - H}$ bonds. The N atom is electronegative, and the H atom in $\ce{N - H}$ can form a hydrogen bond with the lone pair on N of another methanimine molecule. So, the answer is "yes".
• Between the compound and water: Water has $\ce{O - H}$ bonds. The H in $\ce{N - H}$ of methanimine can form a hydrogen bond with the lone pair on O of water, and the H in $\ce{O - H}$ of water can form a hydrogen bond with the lone pair on N of methanimine. So, the answer is "yes".

Final Answers (Filling the table)

compound	Between molecules of the compound?	Between molecules of the compound and molecules of water?
hypobromous acid	yes	yes
methanimine	yes	yes

Answer:

To determine hydrogen - bonding, we use the rule: A hydrogen bond occurs when a hydrogen atom is bonded to a highly electronegative atom (N, O, F) and is in close proximity to another electronegative atom with a lone pair of electrons.

Methylamine ($\ce{CH3NH2}$)

• Between molecules of the compound: The structure has $\ce{N - H}$ bonds. The N atom is electronegative, and the H atom in $\ce{N - H}$ can form a hydrogen bond with the lone pair on N of another methylamine molecule. So, the answer is "yes".
• Between the compound and water: Water has $\ce{O - H}$ bonds. The H in $\ce{N - H}$ of methylamine can form a hydrogen bond with the lone pair on O of water, and the H in $\ce{O - H}$ of water can form a hydrogen bond with the lone pair on N of methylamine. So, the answer is "yes".

Hypobromous acid ($\ce{HBrO}$)

• Between molecules of the compound: The structure has $\ce{O - H}$ bonds. The O atom is electronegative, and the H atom in $\ce{O - H}$ can form a hydrogen bond with the lone pair on O of another $\ce{HBrO}$ molecule. So, the answer is "yes".
• Between the compound and water: Water has $\ce{O - H}$ bonds. The H in $\ce{O - H}$ of $\ce{HBrO}$ can form a hydrogen bond with the lone pair on O of water, and the H in $\ce{O - H}$ of water can form a hydrogen bond with the lone pair on O of $\ce{HBrO}$. So, the answer is "yes".

Methanimine ($\ce{H2C = NH}$)

• Between molecules of the compound: The molecule has $\ce{N - H}$ bonds. The N atom is electronegative, and the H atom in $\ce{N - H}$ can form a hydrogen bond with the lone pair on N of another methanimine molecule. So, the answer is "yes".
• Between the compound and water: Water has $\ce{O - H}$ bonds. The H in $\ce{N - H}$ of methanimine can form a hydrogen bond with the lone pair on O of water, and the H in $\ce{O - H}$ of water can form a hydrogen bond with the lone pair on N of methanimine. So, the answer is "yes".

Final Answers (Filling the table)

compound	Between molecules of the compound?	Between molecules of the compound and molecules of water?
hypobromous acid	yes	yes
methanimine	yes	yes