Calculate the Bi^3+ at the following points on the titration of 25cm3 of 0.02M Bi^3+ solution with 0.02M of EDTA at pH=2. After the addition of:
a. 10cm3
b. 24cm3
c. 25cm3
d.26cm3
e. 30cm3.
(Given: stability constant = 10^27.5, and alpha = 10^15.5)
Please I need quick reply. Thanks
To calculate the concentration of Bi^3+ at each point during the titration, you need to consider the reaction between Bi^3+ and EDTA.
The reaction can be represented as follows:
Bi^3+ + EDTA ⇌ BiEDTA
At the start of the titration, you have 25 cm^3 of a 0.02 M Bi^3+ solution. This means you have 0.02 moles of Bi^3+ in the solution.
a. After the addition of 10 cm^3 of 0.02 M EDTA:
The moles of EDTA added can be calculated using the formula:
moles = concentration × volume
moles of EDTA = 0.02 M × 0.01 L (10 cm^3 = 0.01 L) = 0.0002 moles
Since the reaction between Bi^3+ and EDTA is 1:1, the moles of Bi^3+ reacted with the EDTA are also 0.0002 moles.
To calculate the remaining moles of Bi^3+ in the solution, subtract the moles reacted from the initial moles:
Remaining moles of Bi^3+ = Initial moles - moles reacted = 0.02 moles - 0.0002 moles = 0.0198 moles
To determine the concentration of Bi^3+ in the remaining volume, divide the moles by the remaining volume:
Concentration of Bi^3+ = Remaining moles / Remaining volume = 0.0198 moles / 0.015 L (25 cm^3 - 10 cm^3 = 15 cm^3 = 0.015 L) = 1.32 M
b. After the addition of 24 cm^3 of 0.02 M EDTA:
Following the same steps, you will find the final concentration of Bi^3+ to be 0.0136 M.
c. After the addition of 25 cm^3 of 0.02 M EDTA:
Here, the volume of the solution is equal to the initial volume, so the concentration of Bi^3+ will be the same as the initial concentration, which is 0.02 M.
d. After the addition of 26 cm^3 of 0.02 M EDTA:
The volume of EDTA exceeds the initial volume, resulting in excess EDTA. As a result, all the Bi^3+ will react with the EDTA, and the concentration of Bi^3+ will be zero.
e. After the addition of 30 cm^3 of 0.02 M EDTA:
Similar to the previous case, all the Bi^3+ will react with the excess EDTA, and the concentration of Bi^3+ will be zero.
Remember to consider the stability constant and alpha values provided to calculate the stability of the complex formed (BiEDTA).