Question

4.
h-cl:
polar or nonpolar?
forces present:
5.
:cl:
:cl-c-cl:
:cl:
polar or nonpolar?
forces present:

Explanation:

Problem 4 (HCl)

Step1: Analyze Bond Polarity

HCl has a covalent bond between H and Cl. Cl is more electronegative than H, so the bond is polar (electrons are pulled more toward Cl).

Step2: Molecular Geometry and Dipole

The molecule is linear (two atoms). The polar bond creates a net dipole moment (since there's no symmetry to cancel it). So the molecule is polar.

Step3: Forces Present

Forces: London dispersion forces (present in all molecules) and dipole - dipole forces (due to the polar bond, as the molecule has a permanent dipole). Also, since it's a covalent molecule, no ionic bonds.

Step1: Bond Polarity

C - Cl bonds are polar (Cl is more electronegative than C).

Step2: Molecular Geometry and Dipole Cancellation

The molecule has a tetrahedral geometry. The four C - Cl bonds are symmetrically arranged around the central C atom. The dipole moments of the individual C - Cl bonds cancel each other out (vector sum of dipoles is zero) due to the symmetry. So the molecule is nonpolar.

Step3: Forces Present

Forces: London dispersion forces (present in all molecules). Since the molecule is nonpolar (net dipole moment zero), there are no dipole - dipole forces. Also, no ionic bonds.

Answer:

Polar; Forces Present: London dispersion forces, dipole - dipole forces

Problem 5 (CCl₄)