what is the formula to find the %concentration of Hcl in w/v, If a bottle of Hcl labeled as : Hydrochloric Acid, 6 M, Laboratory Grade, 500 mL,
I never used a formula. If you have 500 mL of a 6 M solution you must have 500 mL that has 6 mols/L of solution.
Percent w/v is defined as grams solute/100 mL of solution; therefore, you must have 3 mols HCl/500 mL. Three (3) mols is 3(36.5 g/mol) = 109.5 g/500 mL or 109.5 x (100/500) = 2.19/100 mL or 2.19%
The formula is (grams solute/100 mL solution) = % solute w/v or
(grams solute/1 mL solution)*100 = % solute w/v
There is an easier way to do this. Remember a 6 M solution is 6 mols/L so % w/v = (6*36.5)/10 so the formula is M*molar mass/10 = % w/v
Hold up on that answer above. I'm not satisfied with it. It will give you an answer that is close. The definitions I've found on the web disagree. I believe the correct definition of % w/v is grams solute/100 grams SOLVENT as opposed to 100 g SOLUTION.
To find the percentage concentration of HCl in w/v (weight/volume), you need to know the amount of HCl present in a given volume. In the case of the given bottle of HCl, it is labeled as "6 M" which stands for 6 molar concentration.
Molarity (M) is defined as the number of moles of solute per liter of solution. Therefore, a 6 M solution of HCl contains 6 moles of HCl per liter of solution. However, in this case, we have a 500 mL (0.5 L) bottle of HCl, not a liter.
To calculate the moles of HCl in the given bottle, you can use the formula:
moles of solute = molarity × volume (in liters)
moles of HCl = 6 M × 0.5 L
moles of HCl = 3 moles
Now that we have the number of moles of HCl, we can calculate the grams of HCl in the solution using its molar mass. The molar mass of HCl is approximately 36.46 g/mol.
grams of solute = moles of solute × molar mass
grams of HCl = 3 moles × 36.46 g/mol
grams of HCl = 109.38 g
Now we have the weight of the solute (HCl), which is 109.38 grams, and the volume of the solution (0.5 L).
To find the percentage concentration in w/v, we divide the weight of the solute by the volume of the solution and multiply by 100:
% concentration (w/v) = (weight of solute / volume of solution) × 100
% concentration (w/v) = (109.38 g / 0.5 L) × 100
% concentration (w/v) = 218.76%
Therefore, the percentage concentration of HCl in the given bottle is 218.76% w/v.