For which of the following compounds is hydrogen bonding the main intermolecular force?
Question 29 options:
a) BH3
b) CH4
c) HCN
d) CH2F2
e) CH3NH3
The correct answer is e) CH3NH3.
Hydrogen bonding occurs when a hydrogen atom is bonded to a highly electronegative atom (such as nitrogen, oxygen, or fluorine) and is attracted to another electronegative atom in a nearby molecule. CH3NH3, also known as methylamine, has a hydrogen atom bonded to a nitrogen atom, which can form hydrogen bonds with other electronegative atoms. The other compounds listed do not have hydrogen atoms bonded to electronegative atoms that can participate in hydrogen bonding.
To determine which compound has hydrogen bonding as the main intermolecular force, we need to consider the presence of hydrogen atoms bonded to highly electronegative elements like oxygen, nitrogen, or fluorine. Hydrogen bonding occurs when hydrogen is bonded directly to one of these electronegative elements.
Let's analyze each compound:
a) BH3: Boron does not have high electronegativity, so hydrogen bonding is unlikely to occur.
b) CH4: Carbon does not have high electronegativity, so hydrogen bonding is unlikely to occur.
c) HCN: The hydrogen atom in HCN is bonded to nitrogen, which is electronegative. Hydrogen bonding is possible in this compound.
d) CH2F2: Although fluorine is highly electronegative, there are no hydrogen atoms bonded directly to fluorine in this compound. Therefore, hydrogen bonding is unlikely to occur.
e) CH3NH3: The hydrogen atoms in CH3NH3 are bonded to nitrogen, which is electronegative. Hydrogen bonding is possible in this compound.
Based on this analysis, the compounds that can exhibit hydrogen bonding as the main intermolecular force are HCN and CH3NH3.
Therefore, the correct answer is:
c) HCN
e) CH3NH3