Respuesta :
The question is incomplete, complete question is ;
Allura Red (AR) has a concentration of 21.22 ppm. What is this is micro moles per liter? Report the precise concentration of the undiluted stock solution #1 of AR in micromoles per liter. This is your most concentrated (undiluted) standard solution for which you measured the absorbance. Use 3 significant figures. Molarity (micro mol/L) =
Answer:
The molarity of the solution of allura red is 42.75 micro moles per Liter.
Explanation:
The ppm is the amount of solute (in milligrams) present in kilogram of a solvent. It is also known as parts-per million.
To calculate the ppm of oxygen in sea water, we use the equation:
[tex]\text{ppm}=\frac{\text{Mass of solute}}{\text{Mass of solution}}\times 10^6[/tex]
Both the masses are in grams.
We are given:
The ppm concentration of allura red = 21.22 ppm
This means that 21.22 mg of allura red was present 1 kg of solution.
Mass of Allura red = 21.22 mg = [tex]21.22\times 0.001 g[/tex]
1 mg = 0.001 g
Mass of solution = 1 kg = 1000 g
Density of the solution = Density of water = d = 1.00 g/mL
( since solution has very small amount of solute)
Volume of the solution :
[tex]=\frac{1000 g}{1.00 g/mL}=1000 mL[/tex]
1000 mL = 1 L
Volume of the solution, V = 1 L
Moles of Allura red = [tex]\frac{21.22\times 0.001 g}{496.42 g/mol}=4.275\times 10^{-5} mol=4.275\times 10^{-5}\times 10^{6} \mu mole[/tex]
Molarity of the solution ;
[tex]=\frac{\text{Moles of solute}}{\text{Volume of solution(L)}}[/tex]
[tex]M=\frac{4.275\times 10^{-5}\times 10^6 \mu mol}{1 L}=42.75 \mu mol/L[/tex]
The molarity of the solution of allura red is 42.75 micro moles per Liter.
