Answer:
Among the pairs listed, the pair of elements most likely to form an ionic bond is **Br and O** (Bromine and Oxygen).
Ionic bonds form between elements with significantly different electronegativities. Electronegativity is a measure of an atom's ability to attract and hold onto electrons. In general, when the electronegativity difference between two elements is large, an ionic bond is more likely to form.
Looking at the electronegativity values:
- Bromine (Br) has an electronegativity of around 2.96.
- Oxygen (O) has an electronegativity of around 3.44.
The electronegativity difference between Br and O is relatively large, indicating that Br and O are more likely to form an ionic bond compared to the other pairs listed.
