Sure! To show that each of the given species can act as a Brønsted-Lowry base, we need to demonstrate that they can accept a proton (H⁺). Here's the detailed step-by-step solution for each species:
### (a) Water ([tex]\( \text{H}_2\text{O} \)[/tex])
Water ([tex]\( \text{H}_2\text{O} \)[/tex]) can accept a proton to form the hydronium ion:
[tex]\[ \text{H}_2\text{O} (l) + \text{H}^+ (aq) \rightarrow \text{H}_3\text{O}^+ (aq) \][/tex]
### (b) Hydroxide ion ([tex]\( \text{OH}^- \)[/tex])
The hydroxide ion ([tex]\( \text{OH}^- \)[/tex]) can accept a proton to form water:
[tex]\[ \text{OH}^- (aq) + \text{H}^+ (aq) \rightarrow \text{H}_2\text{O} (l) \][/tex]
### (c) Ammonia ([tex]\( \text{NH}_3 \)[/tex])
Ammonia ([tex]\( \text{NH}_3 \)[/tex]) can accept a proton to form the ammonium ion:
[tex]\[ \text{NH}_3 (aq) + \text{H}^+ (aq) \rightarrow \text{NH}_4^+ (aq) \][/tex]
### (d) Cyanide ion ([tex]\( \text{CN}^- \)[/tex])
The cyanide ion ([tex]\( \text{CN}^- \)[/tex]) can accept a proton to form hydrogen cyanide:
[tex]\[ \text{CN}^- (aq) + \text{H}^+ (aq) \rightarrow \text{HCN} (aq) \][/tex]
### (e) Sulfide ion ([tex]\( \text{S}^{2-} \)[/tex])
The sulfide ion ([tex]\( \text{S}^{2-} \)[/tex]) can accept a proton to form the hydrogen sulfide ion:
[tex]\[ \text{S}^{2-} (aq) + \text{H}^+ (aq) \rightarrow \text{HS}^- (aq) \][/tex]
### (f) Dihydrogen phosphate ion ([tex]\( \text{H}_2\text{PO}_4^- \)[/tex])
The dihydrogen phosphate ion ([tex]\( \text{H}_2\text{PO}_4^- \)[/tex]) can accept a proton to form phosphoric acid:
[tex]\[ \text{H}_2\text{PO}_4^- (aq) + \text{H}^+ (aq) \rightarrow \text{H}_3\text{PO}_4 (aq) \][/tex]
In each of these reactions, the species acts as a Brønsted-Lowry base by accepting a proton ([tex]\(\text{H}^+\)[/tex]).
