phosphoric acid is the active ingredient in many commercial rust-removing solution.calculate the volume of concentrated phosphoric acid (14.6 mol/L)that must be diluted to prepare 500mL of a 1.25 mol/L solution.
how can i calulate the volume cocentration for this question.... can someone show it to me, step by step plzzzz.... the answer for this question is 42.8 mL ( i looked up in my text book)...thank u :)
YOu are diluting it 14.6/1.25 times, or 11.68 times. That means one part conc acid, 10.68 part water.
YOu want 500ml. What is one part? 500ml/11.68= 42.8ml, the rest water.
There are other more complicated ways to work this.
Just remember, if you are diluting somthing N times, that means 1 part original, and N-1 parts water.
To calculate the volume of concentrated phosphoric acid needed to prepare a 1.25 mol/L solution, you can use the formula:
C1V1 = C2V2
Where:
C1 = concentration of the concentrated phosphoric acid
V1 = volume of the concentrated phosphoric acid
C2 = desired concentration of the final solution
V2 = volume of the final solution
Given values:
C1 = 14.6 mol/L
C2 = 1.25 mol/L
V2 = 500 mL
Step 1: Rearrange the formula to solve for V1:
V1 = (C2 x V2) / C1
Step 2: Substitute the values into the equation:
V1 = (1.25 mol/L x 500 mL) / 14.6 mol/L
Step 3: Cancel out the units and calculate:
V1 = (1.25 x 500) / 14.6
V1 = 68.03 mL
Therefore, you would need to dilute 68.03 mL of concentrated phosphoric acid to prepare 500 mL of a 1.25 mol/L solution.
To calculate the volume of concentrated phosphoric acid required, we can use the equation:
C₁V₁ = C₂V₂
Where:
C₁ = initial concentration of phosphoric acid
V₁ = initial volume of phosphoric acid
C₂ = final concentration of phosphoric acid
V₂ = final volume of phosphoric acid
In this case, the initial concentration (C₁) is 14.6 mol/L, the final concentration (C₂) is 1.25 mol/L, and the final volume (V₂) is 500 mL.
Step 1: Rearrange the equation to solve for V₁:
V₁ = (C₂ * V₂) / C₁
Substitute the given values into the equation:
V₁ = (1.25 mol/L * 500 mL) / 14.6 mol/L
Step 2: Calculate the volume:
V₁ = (1.25 * 500) / 14.6
V₁ = 21.55 mL
So, you would need to dilute approximately 21.55 mL of concentrated phosphoric acid (14.6 mol/L) with a suitable solvent to prepare 500 mL of a 1.25 mol/L solution.
Please note that the answer you found in your textbook may have been rounded to 42.8 mL, which is why there is a slight discrepancy between the two values.