What is the molality of a 30.0% by mass hydrochloric acid solution ? The density of the solution is 1.0980g/mol.
Well, well, well, looks like we have a math problem here. Let's dive into it, shall we?
First things first, we need to convert that pesky percentage into a decimal. So, 30.0% becomes 0.30. Bravo, you did it!
Now, we can calculate the molality using the formula:
Molality = (moles of solute) / mass of solvent in given kgs
Since we're dealing with mass, we can use the density to find the mass of the solution. Density is mass over volume, so rearranging the formula, we have:
Mass = density × volume
Guess what? We're given the density (1.0980 g/mL), but we still need the volume. Without that, we're stuck in a mathematical limbo. No worries though, my friend. Once you have the volume of the solution, you can simply convert it to kilograms by dividing by 1000. Problem solved!
Finally, with the volume and mass of the solution in hand, you can proceed to calculate molality using the formula mentioned earlier.
Now, go get that volume, convert it to kilograms, and crunch those numbers! You got this!
To find the molality (m) of a solution, you need to know the moles of solute and the mass of solvent.
Step 1: Determine the moles of hydrochloric acid (HCl).
To find the moles of HCl, you need to convert the percent by mass to grams.
Assuming you have 100g of the solution, 30.0% by mass means you have 30.0g of HCl.
Step 2: Determine the mass of the solvent (water).
Since the density of the solution is given, you can use it to find the volume and then the mass of the solution.
Density = mass/volume
1.0980 g/mL = mass/100 mL
mass = (1.0980 g/mL)(100 mL) = 109.80 g
Step 3: Calculate the molality (m).
Molality is defined as moles of solute per kilogram of solvent.
The molality (m) can be calculated using the following formula:
m = moles of solute / mass of solvent (in kg)
First, convert the mass of solvent to kilograms:
109.80 g = 0.10980 kg
m = (30.0 g HCl) / (0.10980 kg H2O) = 273.44 mol/kg
Therefore, the molality of the 30.0% by mass hydrochloric acid solution is 273.44 mol/kg.
To find the molality of a solution, you need to know the mass of the solute (in this case, hydrochloric acid) and the mass of the solvent (in this case, the solution).
The given information states that the hydrochloric acid solution is 30.0% by mass. This means that for every 100 grams of the solution, 30 grams are hydrochloric acid.
To calculate the mass of the hydrochloric acid in the solution, you can assume that you have 100 grams of the solution. Hence, the mass of hydrochloric acid would be 30 grams.
The density of the solution is given as 1.0980 g/mL. Since the density is a measure of mass per unit volume, you can consider 100 mL of the solution (which is equivalent to 100 grams due to the density).
Now that you have the mass of the solute (hydrochloric acid) and the mass of the solvent (solution), you can calculate the molality.
Molality (m) is defined as the number of moles of solute per kilogram of solvent. To calculate it, follow these steps:
Step 1: Convert the mass of solute from grams to moles.
The molar mass of hydrochloric acid (HCl) is the sum of the atomic masses of hydrogen (H) and chlorine (Cl), which is approximately 1 g/mol + 35.5 g/mol = 36.5 g/mol.
To convert grams of hydrochloric acid to moles, divide the mass (in grams) by the molar mass of HCl.
30 g of HCl ÷ 36.5 g/mol ≈ 0.82 mol
Step 2: Convert the mass of the solvent from grams to kilograms.
Since we are using 100 grams of the solution, which is equal to 100 mL, and the density is 1.0980 g/mL, the mass of the solvent (solution) is also 100 grams.
To convert grams of the solution to kilograms, divide the mass (in grams) by 1000.
100 g of solution ÷ 1000 ≈ 0.1 kg
Step 3: Calculate the molality.
Divide the moles of solute by the kilograms of solvent.
0.82 mol ÷ 0.1 kg = 8.2 mol/kg
Therefore, the molality of the 30.0% by mass hydrochloric acid solution is approximately 8.2 mol/kg.
molality = moles HCl/Kg Solvent
Given 30% Soln by mass = 30gHCl/100gSoln
Moles HCl = (30g/36g/mol) = 0.833mole
Kg Solvent = (100gSoln/1.098g/ml) = 91.1ml = 91.1gms Soln(1.10g/ml 30%HClsoln*)= 100.21gms of 30%HCLSoln = 0.1002Kg Soln = 60%(0.1002Kg) = 0.60(0.1002)Kg Solvent = 0.0601Kg Solvent
*specific gravity of 30%HCl aqueous soln = 1.10 = 1.10g/ml if solvent is HOH.
molality = (0.833moleHCl)/(0.0601KgSolvent)
=13.85 molal HCl soln