Question

1 multiple choice 2 points
two elements, x and y, have electronegativities of 3.0 and 0.9, respectively.
which statement best explains the type of bond expected to form between x and y?
a polar covalent bond will form because the electronegativity difference is moderate, creating partial charges on each atom.
a metallic bond will form because both atoms have low electronegativity and freely share valence electrons.
a nonpolar covalent bond will form because the electronegativity difference is small, so electrons are shared equally.
an ionic bond will form because the electronegativity difference is large, causing one atom to transfer electrons to the other.
clear my selection

Explanation:

Step1: Calculate electronegativity difference

The formula for electronegativity difference ($\Delta \text{EN}$) is $\Delta \text{EN}=\vert \text{EN}_X-\text{EN}_Y\vert$. Given $\text{EN}_X = 3.0$ and $\text{EN}_Y=0.9$, then $\Delta \text{EN}=\vert3.0 - 0.9\vert=2.1$.

Step2: Analyze bond - type based on electronegativity difference

• For non - polar covalent bonds: $\Delta \text{EN}<0.5$.
• For polar covalent bonds: $0.5\leq\Delta \text{EN}<1.7$.
• For ionic bonds: $\Delta \text{EN}\geq1.7$. Metallic bonds occur between metal atoms (not relevant here as we are comparing two atoms based on electronegativity difference for a binary compound). Since $\Delta \text{EN} = 2.1\geq1.7$, electrons will be transferred from the atom with lower electronegativity (Y) to the atom with higher electronegativity (X).

Answer:

D. An ionic bond will form because the electronegativity difference is large, causing one atom to transfer electrons to the other.