A 36.0mL sample of 1.20 M KBr and a 56.0mL sample of 0.700 M KBr are mixed. The solution is then heated to evaporate water until the total volume is 60.0mL. What is the molarity of the KBr in the final solution?
To find the molarity of KBr in the final solution, we need to calculate the moles of KBr in each sample and then determine the total moles of KBr in the final solution.
Step 1: Calculate the moles of KBr in the first sample.
Using the formula: moles = concentration × volume
moles1 = 1.20 M × 36.0 mL = 43.2 mmol (millimoles)
Step 2: Calculate the moles of KBr in the second sample.
moles2 = 0.700 M × 56.0 mL = 39.2 mmol
Step 3: Determine the total moles of KBr.
total moles = moles1 + moles2
total moles = 43.2 mmol + 39.2 mmol = 82.4 mmol
Step 4: Calculate the molarity of KBr in the final solution.
molarity = moles / volume
molarity = 82.4 mmol / 60.0 mL = 1.37 M
Therefore, the molarity of KBr in the final solution is 1.37 M.
To find the molarity of KBr in the final solution, we first need to calculate the moles of KBr in each sample.
For the 36.0 mL sample of 1.20 M KBr:
Molarity (M) is defined as moles of solute divided by liters of solution.
moles = Molarity x Volume (in liters)
moles = 1.20 M x 0.0360 L = 0.0432 mol
For the 56.0 mL sample of 0.700 M KBr:
moles = 0.700 M x 0.0560 L = 0.0392 mol
Next, we need to determine the total moles of KBr in the solution by adding the moles from both samples.
Total moles of KBr = 0.0432 mol + 0.0392 mol = 0.0824 mol
Finally, we calculate the molarity of KBr in the final solution by dividing the total moles by the final volume.
Molarity = moles / Volume (in liters)
Molarity = 0.0824 mol / 0.0600 L = 1.373 M
Therefore, the molarity of KBr in the final solution is 1.373 M.