Calculate the concentration of ions in the following saturated solutions.
(a) [I −] in AgI solution with [Ag+] = 8.1 10-9 M
(b) [Al3+] in Al(OH)3 solution with [OH −] = 1.8 10-9 M
a)
AgI ==> Ag^+ + I^-
Ksp = ? = (Ag^+)(I^-)
Substitute Ksp and Ag^+ and solve for I^-
In b don't forget to cube the OH^-
To calculate the concentration of ions in a saturated solution, you need to know the balanced chemical equation for the dissociation of the compound in water.
(a) In the case of AgI, it dissociates according to the following balanced chemical equation:
AgI (s) ⇌ Ag+ (aq) + I- (aq)
To find the concentration of I- ions, we need to determine the molar ratio of AgI to I-. From the balanced equation, we can see that one mole of AgI produces one mole of I-. Therefore, the concentration of I- ions is equal to the concentration of Ag+ ions, which is given as 8.1 x 10^-9 M.
So, the concentration of I- ions in the AgI solution is 8.1 x 10^-9 M.
(b) In the case of Al(OH)3, it dissociates according to the following balanced chemical equation:
Al(OH)3 (s) ⇌ Al3+ (aq) + 3OH- (aq)
To find the concentration of Al3+ ions, we need to determine the molar ratio of Al(OH)3 to Al3+. From the balanced equation, we can see that one mole of Al(OH)3 produces one mole of Al3+. Therefore, the concentration of Al3+ ions is also equal to the concentration of OH- ions, which is given as 1.8 x 10^-9 M.
So, the concentration of Al3+ ions in the Al(OH)3 solution is 1.8 x 10^-9 M.