A solution is prepared by placing 23.9 g of KCl in a 0.500 L volumetric flask and adding water to dissolve the solid, then filling the flask to the mark. What is the molarity of an AgNO3 solution if 27.9 mL of the KCl solution react exactly with 45.0 mL of the AgNO3 solution?
Well, that's quite a chemistry problem you have there! Let me grab my goggles and put on my lab coat.
First, let's calculate the moles of KCl in the 27.9 mL solution. To do this, we need to know the molar mass of KCl, which is about 74.55 g/mol.
So, moles of KCl = mass of KCl / molar mass of KCl
= 23.9 g / 74.55 g/mol
That should give us the number of moles of KCl in the solution. Now, since the reaction between KCl and AgNO3 is a 1:1 ratio, the number of moles of AgNO3 in the 45.0 mL solution should also be the same.
Lastly, to find the molarity of AgNO3, we divide the moles of AgNO3 by the volume of the solution in liters.
Are you still following along? I promise I won't make any explosions!
To find the molarity of the AgNO3 solution, we can use the following formula:
Molarity (M) = moles of solute / volume of solution in liters
Let's break down the problem step by step:
Step 1: Find the moles of KCl used.
To convert the mass of KCl to moles, we need to use the molar mass of KCl. The molar mass of KCl is 74.55 g/mol.
moles of KCl = (mass of KCl) / (molar mass of KCl)
moles of KCl = 23.9 g / 74.55 g/mol
moles of KCl = 0.321 mol
Step 2: Determine the number of moles of AgNO3 used.
To find the moles of AgNO3 used, we can use the stoichiometry of the reaction. From the balanced equation, we know that the reaction is 1:1 between KCl and AgNO3.
moles of AgNO3 = moles of KCl used (as they react in a 1:1 ratio)
moles of AgNO3 = 0.321 mol
Step 3: Find the volume of the AgNO3 solution in liters.
We have been given the volume of the AgNO3 solution as 45.0 mL. We need to convert it to liters.
volume of AgNO3 solution = 45.0 mL x (1 L / 1000 mL)
volume of AgNO3 solution = 0.045 L
Step 4: Calculate the molarity of the AgNO3 solution.
Now, we can substitute the given values into the formula:
Molarity (M) = moles of solute / volume of solution in liters
Molarity of AgNO3 = 0.321 mol / 0.045 L
Molarity of AgNO3 = 7.13 M
Therefore, the molarity of the AgNO3 solution is 7.13 M.
To find the molarity of the AgNO3 solution, we first need to determine the number of moles of KCl that reacted with AgNO3.
We start by finding the number of moles of KCl. The molar mass of KCl is 74.55 g/mol.
Number of moles of KCl = Mass of KCl / Molar mass of KCl
= 23.9 g / 74.55 g/mol
= 0.32 mol
Next, we need to determine the ratio between KCl and AgNO3 in the balanced chemical equation. The balanced equation is:
2 AgNO3 + KCl -> 2 AgCl + KNO3
According to the balanced equation, 2 moles of AgNO3 react with 1 mole of KCl.
Using the ratio above, we can calculate the number of moles of AgNO3 that reacted:
Number of moles of AgNO3 = (Number of moles of KCl) / 2
= 0.32 mol / 2
= 0.16 mol
Now, we can calculate the molarity of the AgNO3 solution:
Molarity = Number of moles / Volume in liters
Since we are given the volume of the AgNO3 solution in milliliters, we need to convert it to liters by dividing by 1000.
Volume of AgNO3 solution = 45.0 mL / 1000
= 0.045 L
Molarity = Number of moles / Volume in liters
= 0.16 mol / 0.045 L
= 3.56 M
So, the molarity of the AgNO3 solution is 3.56 M.
mols KCl = grams/molar mass = approx 0.32 g but you need a more exact number for this and all of the estimates that follow.
M KCl = 0.32/0.5L = about 0.64
Then mL x M = mL x M
27.3 x 0.64 = 45.0 x M AgNO3
Solve for M AgNO3.
The mL x M = mL x M works because the equation is 1:1.
AgNO3 + KCl ==> AgCl + KNO3