the concetration of HCl in a commercial concetrated HCl solution is given as 37%(W/W). calculate the molarity., normality of HCl in the solution . prepare 100.ml of 1N solution of HCl
the concetration of HCl in a commercial concetrated HCl solution is given as 37%(W/W). calculate the molarity
from the weight concentration.
37gHCl/(37gHCl+63gH2O)
molality=(37/36.5)/.063=16.1
Molarity=(37/36.5)/.1=10.1=Normality
prepare 100ml 1N
ok, you want to dilute it 10.1 times, which means one part conc acid, and 9.1 parts water
1part=10.1ml acid
9 parts=90.9ml water
so add the acid to water (Always add acid to water, slowly, stirring, under a hood).
I think this is a flawed problem. The density isn't given and without that one doesn't know the volume of the solution; therefore I don't think an accurate molarity can be calculated. A 37% solution of HCl has a molarity of very close to 12 M and the density is about (from memory) 1.19 g/mL.
1.19 g/mL x 1000 mL x 0.37 x (11/36.5) = 12 M
To calculate the molarity and normality of a solution, we need to know the concentration in terms of percent by weight (% w/w) or percent by volume (% v/v), along with the molecular weight of the solute.
In this case, we have a concentrated HCl solution with a concentration of 37% (w/w). To calculate the molarity, we need to know the molecular weight of HCl, which is 36.46 g/mol.
1. Calculating the molarity (M):
- First, we need to determine the mass of HCl in the solution. Assuming we have 100 g of the concentrated HCl solution, 37% (w/w) of HCl is present. So, the mass of HCl is:
Mass of HCl = 37 g (since 37% of 100 g is 37 g)
- Now, we can calculate the number of moles of HCl by dividing the mass of HCl by its molecular weight:
Moles of HCl = Mass of HCl / Molecular weight of HCl
= 37 g / 36.46 g/mol
- Finally, we calculate the molarity by dividing the moles of HCl by the volume of the solution in liters (100 mL = 0.1 L):
Molarity (M) = Moles of HCl / Volume of solution (in L)
= (37 g / 36.46 g/mol) / 0.1 L
2. Calculating the normality (N):
- The normality of a solution measures the number of equivalents of the solute, which is the number of reactive particles per molecule in a chemical reaction. Since HCl is monoprotic, the number of equivalents is the same as the number of moles of HCl.
- Therefore, the normality is equal to the molarity:
Normality (N) = Molarity (M)
Now let's calculate the molarity and prepare the 1N solution of HCl:
1. First, calculate the molarity (M):
Molarity (M) = (37 g / 36.46 g/mol) / 0.1 L
= 10.12 M
2. To prepare 100 mL of 1N solution of HCl, we need to calculate the amount of HCl required:
Moles of HCl = Normality (N) × Volume of solution (in L)
= 1 eq/L × 0.1 L
The moles of HCl calculated in the previous step can be used to find the mass of HCl required using its molar mass:
Mass of HCl = Moles of HCl × Molar mass of HCl
Finally, dissolve the calculated mass of HCl in a sufficient amount of water to make a total volume of 100 mL.
Note: Handling concentrated HCl solutions can be hazardous, and it is essential to follow appropriate safety precautions and protocols when working with these chemicals.