Answer:
99.4%
Step-by-step explanation:
The percent ionic character of a molecule can be calculated using the equation:
% ionic character = (observed dipole moment / dipole moment for a purely ionic bond) × 100%
The dipole moment for a purely ionic bond is calculated using the formula:
μ = q × d
where μ is the dipole moment, q is the charge on each ion, and d is the distance between the ions. For X–Y, we can assume that X has a partial negative charge (-δ) and Y has a partial positive charge (+δ), so the dipole moment for a purely ionic bond would be:
μionic = q × d = δ × (charge on X + charge on Y) × bond length
Since we don't know the charges on X and Y, we can't calculate μionic exactly. However, we can estimate it by assuming that the charges are equal and opposite, so that δ = (1/2) × 1.55 D / 151 pm = 5.15 × 10^-30 C·m. Using this value, we get:
μionic ≈ 2 × 5.15 × 10^-30 C·m × 151 pm = 1.56 D
Now we can plug in the values for X–Y:
% ionic character = (1.55 D / 1.56 D) × 100% ≈ 99.4%
Therefore, X–Y has a very high percent ionic character, indicating that it is mostly an ionic compound rather than a covalent one.