Respuesta :
Explanation:
According to Arrhenius, bases are the species which dissociate to give hydroxide ions, that is, [tex]OH^{-}[/tex].
For example, [tex]NaOH + H_{2}O \rightarrow Na^{+} + OH^{-}[/tex]
Arrhenius acids are the species which dissociate to give hydrogen ions, that is, [tex]H^{+}[/tex].
For example, [tex]CH_{3}COOH + H_{2}O \rightleftharpoons H_{3}O^{+} + CH_{3}COO^{-}[/tex]
In the given example, HCN is donating the hydrogen ion therefore, it is an acid whereas [tex]HPO^{2-}_{4}[/tex] is accepting the hydrogen ions so it acts as a base.
Now, standard [tex]\Delta G^{o}[/tex] values of the given species are as follows.
HCN = 124.7 kJ/mol, [tex]HPO^{2-}_{4}[/tex] = -1089.3 kJ/mol
[tex]H_{2}PO^{-}_{4}[/tex] = -1130.4 kJ/mol, [tex]CN^{-}[/tex] = 172.4 kJ/mol
Therefore, [tex]\Delta G^{o}[/tex] of the given reaction will be calculated as follows.
[tex]\Delta G^{o} = \Delta G_{products} - \Delta G_{reactants}[/tex]
= [-1130.4 + 172.4] - [124.7 + (-1089.3)]
= (-958 + 964.6) kJ/mol
= 6.6 kJ/mol
Since, [tex]\Delta G^{o}[/tex] is greater than zero. Hence, the reaction will be non-spontaneous.
