Question

Calculate the molarity of a solution made by dissolving 12.5g of na2cro4 in enough water toform exactly 550 ml of solution

Answer 1

To calculate the molarity of the solution, you need to determine the number of moles of Na2CrO4 in the given mass and then divide it by the volume of the solution in liters. The molarity of the solution is 0.14 M.

Step-by-step explanation:

To calculate the molarity of the solution, we need to first determine the number of moles of Na2CrO4 in the 12.5g. We can use the molar mass of Na2CrO4 to convert the grams to moles. The molar mass of Na2CrO4 is 161.97 g/mol. Using the given volume of the solution (550 mL), we can then calculate the molarity by dividing the moles of solute by the volume of the solution in liters. Molarity (M) = moles of solute / volume of solution (in L).

First, let's calculate the moles of Na2CrO4:
Moles of Na2CrO4 = Mass of Na2CrO4 / Molar mass of Na2CrO4
Moles of Na2CrO4 = 12.5 g / 161.97 g/mol = 0.077 moles

Next, let's convert the volume of the solution to liters:
Volume of solution (in L) = 550 mL / 1000 mL/L = 0.55 L

Finally, let's calculate the molarity:
Molarity (M) = Moles of Na2CrO4 / Volume of solution (in L)
Molarity = 0.077 moles / 0.55 L = 0.14 M