To determine which pair of ions can form an ionic bond with each other, we need to understand the fundamental principle that drives the formation of ionic bonds. An ionic bond is formed between two ions with opposite charges, where one ion is a cation (positively charged) and the other is an anion (negatively charged). This electrostatic attraction between oppositely charged ions is what constitutes an ionic bond.
Let's analyze each given option to see if the ions can form an ionic bond:
1. [tex]$Cu^{+}$[/tex] and [tex]$Ag^{+}$[/tex]:
- Both [tex]$Cu^{+}$[/tex] (Copper ion) and [tex]$Ag^{+}$[/tex] (Silver ion) are positively charged ions (cations).
- Since they both have like charges, they will repel each other and cannot form an ionic bond.
2. [tex]$S^{2-}$[/tex] and [tex]$O^{2-}$[/tex]:
- Both [tex]$S^{2-}$[/tex] (Sulfide ion) and [tex]$O^{2-}$[/tex] (Oxide ion) are negatively charged ions (anions).
- Similarly, having like charges means they will repel each other and cannot form an ionic bond.
3. [tex]$Br^{-}$[/tex] and [tex]$At^{-}$[/tex]:
- [tex]$Br^{-}$[/tex] (Bromide ion) and [tex]$At^{-}$[/tex] (Astatide ion) are also both negatively charged ions (anions).
- Like the previous options, these ions have like charges and will repel each other, hence they cannot form an ionic bond.
4. [tex]$Li^{+}$[/tex] and [tex]$Br^{-}$[/tex]:
- [tex]$Li^{+}$[/tex] (Lithium ion) is a positively charged ion (cation).
- [tex]$Br^{-}$[/tex] (Bromide ion) is a negatively charged ion (anion).
- Since [tex]$Li^{+}$[/tex] and [tex]$Br^{-}$[/tex] have opposite charges, they will attract each other, thus forming an ionic bond.
Based on the analysis, the pair of ions that can form an ionic bond with each other is the pair with unlike charges: [tex]$Li^{+}$[/tex] and [tex]$Br^{-}$[/tex]. Therefore, the correct answer is the fourth pair:
- [tex]$Li^{+}$[/tex] and [tex]$Br^{-}$[/tex]: They have unlike charges and can form an ionic bond.
