What is the molarity of the final solution if 2.00mL of the 5.00 M stock solution is diluted to 10.00mL to make solution A? Solution A then undergoes a second dilution by taking 3.00mL solution A and diluting it to 25mL.
5 times the volume, so 1/5 the molarity.
similarly for the 2nd part.
To find the molarity of the final solution, we can use the concept of dilution.
First, let's calculate the number of moles in the initial solution A before the first dilution:
moles of solute (solution A) = volume of solution A × molarity of solution A
moles of solute (solution A) = 2.00 mL × (5.00 mol/L)
To convert mL to L, divide by 1000:
moles of solute (solution A) = 0.002 L × (5.00 mol/L)
moles of solute (solution A) = 0.01 mol
Now, let's determine the molarity of solution A after the first dilution:
molarity of solution A = moles of solute (solution A) / volume of solution A (after dilution)
The volume of the solution after dilution is 10.00 mL:
molarity of solution A = 0.01 mol / 10.00 mL
Again, convert mL to L:
molarity of solution A = 0.01 mol / 0.010 L
molarity of solution A = 1.00 mol/L
Now, let's move on to the second dilution. We need to calculate the moles of solute in 3.00 mL of solution A:
moles of solute (solution A) = volume of solution A × molarity of solution A
moles of solute (solution A) = 3.00 mL × (1.00 mol/L)
moles of solute (solution A) = 0.003 L × (1.00 mol/L)
moles of solute (solution A) = 0.003 mol
Finally, we can calculate the molarity of the final solution (after the second dilution):
molarity of final solution = moles of solute (solution A) / volume of final solution
The volume of the final solution is given as 25 mL:
molarity of final solution = 0.003 mol / 25 mL
Again, convert mL to L:
molarity of final solution = 0.003 mol / 0.025 L
molarity of the final solution ≈ 0.12 mol/L
Therefore, the molarity of the final solution is approximately 0.12 mol/L.