Physical Developer (PD) is a set of solutions used to develop latent fingerprints on different porous and nonporous surfaces. It is often used to develop fingerprints on currency. Below are FBI recipes for PD. Solution 1 serves as a cleaning solution before using a mixture of solutions 2 and 4 in which the fingerprint is developed due to a redox reaction causing the deposition of metallic silver within the ridges of the fingerprint. Determine the concentration of each ingredient in the four solutions. The final volume for each solution is 1.00 L.
Solution 1: 25.0 g of maleic acid (C4H4O4)
Solution 2: 30.0 g of iron(II) nitrate [ Fe(NO3)2 ]
80.0 g of iron(II) ammonium sulfate [ Fe(NH4)2(SO4)2 ]
20.0 g of citric acid (C6H8O7)
Solution 3: 3.00 g of N-dodecylamine acetate (C14H31NO2)
4.00 g of synperonic-N (skip-this is a mixture)
Solution 4: 200.0 g of silver nitrate
I don't really know where to start in terms of calculations that would help in solving this problem. I can deduce that the metallic silver deposition in the ridges of the fingerprint would obviously contain Ag and an anion from one of the solutions (maybe solution 2). Thanks in advance for any help.
This is a very simple problem. I suspect you are getting trapped from all of the stuff that goes on before the question. Forget everything in the problem except the last two sentences; ie., Determine the concn of each ingredient AND the final volume in each is 1 L. All the rest is just to overwhelm you with information that is of no use..
All are worked alike. Here is what you do.
Step 1. mols of ech ingredient = grams/molar mass = ?
Step 2. M = molarity = mols from step 1/1 L = ?
I also want to point out that the problem DOES NOT say what units are to be used for the concentration. i chose to do them by M because I'm sure that's what the author of the problem meant; however, note that for solution 1 you could have said that (maleic acid) = 25,0 g/L and that would be right. The others could be done similarily, also.
To determine the concentration of each ingredient in the four solutions, you will need to calculate the molarity (M) of each component.
To calculate molarity, you need to know the molar mass (g/mol) of each compound and the volume (L) of the solution.
Let's start with Solution 1:
1. Calculate the molarity of maleic acid (C4H4O4):
- Molar mass of maleic acid (C4H4O4) = 116.07 g/mol
- Volume of Solution 1 = 1.00 L
- Molarity of maleic acid = (25.0 g / 116.07 g/mol) / 1.00 L = 0.215 M
Moving on to Solution 2:
1. Calculate the molarity of iron(II) nitrate (Fe(NO3)2):
- Molar mass of iron(II) nitrate (Fe(NO3)2) = 179.86 g/mol
- Volume of Solution 2 = 1.00 L
- Molarity of iron(II) nitrate = (30.0 g / 179.86 g/mol) / 1.00 L = 0.167 M
2. Calculate the molarity of iron(II) ammonium sulfate (Fe(NH4)2(SO4)2):
- Molar mass of iron(II) ammonium sulfate (Fe(NH4)2(SO4)2) = 392.14 g/mol
- Volume of Solution 2 = 1.00 L
- Molarity of iron(II) ammonium sulfate = (80.0 g / 392.14 g/mol) / 1.00 L = 0.204 M
3. Calculate the molarity of citric acid (C6H8O7):
- Molar mass of citric acid (C6H8O7) = 192.13 g/mol
- Volume of Solution 2 = 1.00 L
- Molarity of citric acid = (20.0 g / 192.13 g/mol) / 1.00 L = 0.104 M
For Solution 3 and Solution 4, the instructions provided do not specify the volumes used or ask for the molarity. Therefore, we cannot calculate the molarity for these two solutions based on the given information.
Note: The molar masses used in the calculations are rounded to two decimal places, but you may need to use the exact values for precise calculations.
To determine the concentration of each ingredient in the four solutions, we need to calculate the molarity (moles per liter) of each component.
Let's start by calculating the moles of each ingredient in Solution 1:
1. Find the molar mass of maleic acid (C4H4O4):
Molar mass of C = 12.01 g/mol
Molar mass of H = 1.01 g/mol
Molar mass of O = 16.00 g/mol
Molar mass of C4H4O4 = (4 × 12.01) + (4 × 1.01) + (4 × 16.00) = 116.07 g/mol
2. Calculate the moles of maleic acid (C4H4O4) in Solution 1:
Moles = Mass / Molar mass
Moles of C4H4O4 = 25.0 g / 116.07 g/mol
Now, let's calculate the molarity of each component in Solution 2:
1. Find the molar mass of iron(II) nitrate [Fe(NO3)2]:
Molar mass of Fe = 55.85 g/mol
Molar mass of N = 14.01 g/mol
Molar mass of O = 16.00 g/mol
Molar mass of Fe(NO3)2 = (1 × 55.85) + (2 × 14.01) + (6 × 16.00) = 179.86 g/mol
2. Calculate the moles of iron(II) nitrate [Fe(NO3)2] in Solution 2:
Moles = Mass / Molar mass
Moles of Fe(NO3)2 = 30.0 g / 179.86 g/mol
3. Repeat the above steps for iron(II) ammonium sulfate [Fe(NH4)2(SO4)2] and citric acid (C6H8O7) in Solution 2.
Next, let's calculate the molarity of each component in Solution 4:
1. Find the molar mass of silver nitrate (AgNO3):
Molar mass of Ag = 107.87 g/mol
Molar mass of N = 14.01 g/mol
Molar mass of O = 16.00 g/mol
Molar mass of AgNO3 = 107.87 + (1 × 14.01) + (3 × 16.00) = 169.87 g/mol
2. Calculate the moles of silver nitrate (AgNO3) in Solution 4:
Moles = Mass / Molar mass
Moles of AgNO3 = 200.0 g / 169.87 g/mol
Finally, Solution 3 components are given in grams, so we need to convert them to moles to calculate the molarity.
Repeat the steps above for N-dodecylamine acetate (C14H31NO2) and synperonic-N in Solution 3.
Once you have calculated the moles of each component for all four solutions, divide the moles by the final volume of each solution, which is 1.00 L, to obtain the concentration (molarity) of each ingredient in the solutions.
Please note that it's important to double-check the calculations and unit conversions to ensure accuracy.