EDTA: 292.2
1. How would you make 250ml's of a 15% EDTA solution
2.How much of solution 1(above)should be used to make 500ml's of a .1% EDTA solution.
1. 15 g EDTA/100 = 15%.
Scale up to 250.
15 g EDTA x (250/100) = ?
2. mL1 x %1 = mL2 x %2
Substitute and solve.
To find the solution to these problems, we need to use the concept of molarity and the formula for calculating the amount of solute needed to make a certain concentration of solution.
Here is how you can approach each problem:
1. How to make 250 ml of a 15% EDTA solution:
To make a solution with a specific percentage, we need to know the weight percent of the solute and the density of the solution. However, you provided the molar mass of EDTA (292.2 g/mol), which means we should use molarity instead.
To proceed, we need to know the molar mass of EDTA and convert it to grams per mole. Given that the molar mass of EDTA is 292.2 g/mol, we can calculate the grams of EDTA needed to prepare a specific molarity (M) and volume (V) of a solution using the formula:
Mass (grams) = Molarity (moles/liter) x Molar Mass (grams/mole) x Volume (liters)
Plugging in the values for the desired molarity (0.15 moles/liter) and volume (0.25 liters) into the formula, we can calculate the mass of EDTA needed:
Mass = 0.15 moles/liter x 292.2 grams/mole x 0.25 liters
Mass = 10.965 grams
Therefore, to make a 250 ml (or 0.25 liters) solution of 15% EDTA, you would need 10.965 grams of EDTA.
2. How much of solution 1 should be used to make 500 ml of a 0.1% EDTA solution:
To calculate this, we will first determine the concentration of EDTA in solution 1 and then use the formula for dilution:
Concentration (c1) x Volume (V1) = Concentration (c2) x Volume (V2)
Given that we made 250 ml of a 15% EDTA solution in solution 1, we can determine the concentration of EDTA:
Concentration (c1) = Mass of EDTA / Volume of solution 1
Concentration (c1) = 10.965 grams / 0.25 liters
Concentration (c1) = 43.86 g/L
Now, we can plug in the values into the dilution formula to find the volume of solution 1 needed:
(c1) x (V1) = (c2) x (V2)
(43.86 g/L) x V1 = (0.1 g/L) x (0.5 L)
V1 = (0.1 g/L) x (0.5 L) / (43.86 g/L)
V1 = 0.001138 L (or 1.138 ml)
Therefore, to make 500 ml of a 0.1% EDTA solution, you would need to use 1.138 ml of the solution prepared in step 1.