The density of a solution of 3.69g KBr in 21.70g H2O is 1.11g/mL. What is the molarity of KBr in the solution.
See your other post above.
0.2M
Mass of solution
= 3.69g + 21.70g
=25.39 g
Volume of solution
= 25.39g / 1.11g/mL
=22.9 mL
= 0.0229 L
Moles KCl
= 3.69 g / 74.5513g/mol
= 0.0494961 mol
Molarity of KCl
= 0.0494961 mol / 0.0229L
= 2.1614 mol/L
Now just do that for KBr instead of KCl i.e change the molecular weight in step 3
Well, aren't you a solution connoisseur! Let's solve this equation and find out the molarity of KBr in this clown-approved solution.
First things first, density is defined as mass over volume. In our case, the density is given as 1.11 g/mL. So, if we divide the mass by the volume, we'll get the concentration of the solution.
The mass of KBr is given as 3.69 g and the mass of H2O is 21.70 g. Since the total volume of the solution is not given, we'll need to calculate it.
Using the given density, we can determine that the volume of the solution is 24.77 mL. (Volume = mass / density)
Now that we have the volume and the mass of KBr, we can calculate its molarity.
Molarity (M) is given by the formula M = moles of solute / liters of solution.
To find moles of solute, we need to convert the mass of KBr to moles using its molar mass.
The molar mass of KBr is approximately 119 g/mol. (Molar mass of K = 39 g/mol, Molar mass of Br = 80 g/mol)
Dividing 3.69 g of KBr by its molar mass, we get approximately 0.031 mol.
Since the volume of the solution is given in mL, we need to convert it to liters. 24.77 mL is equal to 0.02477 L.
Finally, dividing the number of moles (0.031 mol) by the volume in liters (0.02477 L), we get a molarity of approximately 1.25 M.
So, the molarity of KBr in the solution is around 1.25 M. Hope that brings a smile to your face!
To find the molarity of KBr in the solution, we need to first determine the number of moles of KBr present. We can then divide this value by the volume of the solution in liters.
Step 1: Calculate the number of moles of KBr.
The molar mass of KBr is the sum of the atomic masses of potassium (K) and bromine (Br). The atomic mass of potassium is 39.10 g/mol, and the atomic mass of bromine is 79.90 g/mol.
Molar mass of KBr = 39.10 g/mol (K) + 79.90 g/mol (Br) = 119.00 g/mol
To find the moles of KBr, we divide the mass of KBr by its molar mass:
moles of KBr = mass of KBr / molar mass of KBr
moles of KBr = 3.69 g / 119.00 g/mol
Step 2: Calculate the volume of the solution in liters.
The density of the solution is given as 1.11 g/mL. To find the volume of the solution, we divide the mass of the solution by its density:
volume of solution = mass of solution / density of solution
volume of solution = (3.69 g KBr + 21.70 g H2O) / 1.11 g/mL
Step 3: Calculate the molarity of KBr.
Molarity is defined as moles of solute divided by the volume of the solution in liters:
Molarity of KBr = moles of KBr / volume of solution
Now, let's substitute the values into the equation to calculate the molarity of KBr.