Question

question 11 (1 point)
the magnitude of london dispersion forces is proportional to which of the following?
number of single covalent bonds
ionic bonding
number of double covalent bonds
molecular mass of participating molecules
question 12 (1 point)
predict which of the following molecules will demonstrate the least polarity.
clo-
co
secl4
o2

Explanation:

Question 11

London dispersion forces are weak intermolecular forces. They arise due to temporary dipoles in molecules. The larger the molecular mass of a molecule, the more electrons it has. More electrons mean a greater chance of forming temporary dipoles. So, the magnitude of London dispersion forces is proportional to the molecular mass of participating molecules. Single and double covalent bonds are types of intramolecular bonds. Ionic bonding is a type of intramolecular bonding (between ions) and not related to London dispersion forces (which are intermolecular).

• $\text{ClO}^-$: It is an ion. Ions have charge separation and are polar.
• $\text{CO}$: Carbon and oxygen have different electronegativities. There is a significant difference in electronegativity ($\Delta \text{EN}=\text{EN}(O)-\text{EN}(C)=3.44 - 2.55= 0.89$). So, it is a polar molecule.
• $\text{SeCl}_4$: Selenium and chlorine have different electronegativities ($\Delta \text{EN}=\text{EN}(Cl)-\text{EN}(Se)=3.16 - 2.55 = 0.61$). The molecule has a see - saw shape (due to the lone pair on Se), which makes it polar.
• $\text{O}_2$: It is a diatomic molecule with two oxygen atoms. Since both atoms are the same, the electronegativity difference is zero ($\Delta \text{EN}=0$). So, it is a non - polar molecule.

Answer:

molecular mass of participating molecules

Question 12