Question

Is cesium bromide an ionic or covalent compound?

Answer 1

Cesium bromide, `"CsBr"`. is an ionic compound, and can further be classified as a salt

Explanation:

Usually a bond between a metal and a nonmetal is ionic. Cesium is a metal and bromine is a nonmetal. In addition, we can look at the difference in electronegativity between the two elements.

Electronegativity (EN) is the tendency of an atom to attract electrons to itself. Metals tend to have lower ENs than nonmetals.
A difference in electronegativity `(Delta"EN")` of `<0.5` indicates a nonpolar covalent bond. A `Delta"EN"` of `0.5-1.7` indicates a polar covalent bond. A `Delta"EN"` of `>=2.0` indicates an ionic bond. A `Delta"EN"` between `1.7` and `2.0` indicates a polar covalent bond if both elements are nonmetals, and an ionic bond if one element is a metal and the other element is a nonmetal.

Cesium's EN is `0.79`, and bromine's EN is `2.96`. The `Delta"EN"=2.96-0.79=2.7`. Therefore the bond is ionic.

Ionic compounds which do not contain `"H"^+"` (hydrogen ion) or `"OH"^-"` (hydroxide ion) are called salts

For more information:
https://en.wikipedia.org/wiki/Electronegativity