A 5.0ml aliquot of a sample was transferred to a 25.0ml flask and acidified by addition of 2.5ml of 0.1M HClO4 and diluted to mark. 1.0ml of that solution was mixed with 5.0ml of 1 X 10-4M AYR(Aluminum)dye and 15.0ml ethanol in a 25.0ml flask and diluted to mark. What is the concentration of the Al^3+ in the sample.

To determine the concentration of Al^3+ in the sample, we can follow these steps:

1. Calculate the initial moles of HClO4 added to the 5.0ml aliquot of the sample:
Moles HClO4 = concentration (M) × volume (L)
Moles HClO4 = 0.1M × 0.0025L
Moles HClO4 = 2.5 × 10^-4 moles

2. Calculate the total volume of the sample solution after it was transferred to the 25.0ml flask:
Total volume = 5.0ml aliquot + 2.5ml HClO4 + 25.0ml dilution
Total volume = 5.0ml + 2.5ml + 25.0ml
Total volume = 32.5ml

3. Calculate the moles of HClO4 in the total sample solution:
Moles HClO4 = Moles HClO4 added to the aliquot × (Total volume / Aliquot volume)
Moles HClO4 = 2.5 × 10^-4 moles × (32.5ml / 5.0ml)
Moles HClO4 = 1.625 × 10^-3 moles

4. Determine the moles of Al^3+ in the final diluted solution:
Moles Al^3+ = Moles HClO4
Moles Al^3+ = 1.625 × 10^-3 moles

5. Calculate the concentration of Al^3+ in the sample:
Concentration Al^3+ = Moles Al^3+ / Volume of final solution
Concentration Al^3+ = (1.625 × 10^-3 moles) / (25.0ml × 10^-3 L/ml)
Concentration Al^3+ = 6.5 × 10^-2 M

Therefore, the concentration of Al^3+ in the sample is 6.5 × 10^-2 M.

To determine the concentration of Al^3+ in the sample, we will go through the given steps:

Step 1: Calculate the dilution factor for the solution in the 25.0ml flask.

The volume of the aliquot transferred to the flask = 5.0ml
The final volume in the flask after dilution = 25.0ml

Dilution factor = Final volume / Initial volume
Dilution factor = 25.0ml / 5.0ml
Dilution factor = 5.0

Step 2: Calculate the concentration of the solution in the 25.0ml flask.

Let C1 be the concentration of the sample before dilution.
C2 is the concentration of the solution in the 25.0ml flask.

C1 x V1 = C2 x V2

Substituting the values:
C2 = (C1 x V1) / V2
C2 = (C1 x 5.0ml) / 25.0ml
C2 = (C1 / 5.0) M

Step 3: Calculate the concentration of Al^3+ in the final solution.

In the final solution, 1.0ml of the diluted solution is mixed with 5.0ml of 1 X 10^-4M AYR dye and 15.0ml of ethanol.

The volume of Al^3+ from the diluted solution = 1.0ml
The concentration of Al^3+ in the AYR dye = 1 X 10^-4M

The final volume in the flask after dilution = 1.0ml + 5.0ml + 15.0ml = 21.0ml

Using the formula:

C1 x V1 = C2 x V2

Substituting the values:
(C1 / 5.0) M x 1.0 ml = (1 X 10^-4 M) x 21.0 ml

C1 = ((1 X 10^-4 M) x 21.0 ml) / 1.0 ml
C1 = 0.0021 M

Therefore, the concentration of Al^3+ in the sample is 0.0021 M.