Write the positive and negative ions that result when the following compounds are dissolved in aqueous solution:
Na2S (aq):
(NH4)2CO3 (aq):
K2SO4 (aq):
2Na+ (aq) + S2- (aq)
2Na+S2
Na2S (aq):
Positive ion: Na+
Negative ion: S2-
(NH4)2CO3 (aq):
Positive ion: NH4+
Negative ion: CO3^2-
K2SO4 (aq):
Positive ion: K+
Negative ion: SO4^2-
To determine the positive and negative ions that result when compounds dissolve in aqueous solution, we need to consider the dissociation of the compounds into their constituent ions.
1. Na2S (aq):
The compound Na2S dissociates into sodium ions (Na+) and sulfide ions (S2-) in aqueous solution. Therefore, the positive ion is Na+ and the negative ion is S2-.
2. (NH4)2CO3 (aq):
The compound (NH4)2CO3 dissociates into ammonium ions (NH4+) and carbonate ions (CO32-) in aqueous solution. Hence, the positive ion is NH4+ and the negative ion is CO32-.
3. K2SO4 (aq):
The compound K2SO4 dissociates into potassium ions (K+) and sulfate ions (SO42-) in aqueous solution. Therefore, the positive ion is K+ and the negative ion is SO42-.
Remember that when these compounds dissolve in water, they break apart into ions, which are then surrounded by water molecules in a process called hydration. This is why they are denoted as aqueous solutions (aq).