Calculate the mass of oxalic acid needed to prepare 150 ml of 0.442 M C2H2O4.
How many mols do you need? That's M x L = mols.
Then mols = grams/molar mass. You know molar mass and mols, solve for grams.
To calculate the mass of oxalic acid needed to prepare a certain volume and concentration, you need to use the formula:
M = (mols of solute) / (volume of solution in liters)
In this case, you are given the volume of the solution (150 ml) and the molarity (0.442 M), and you need to find the moles of oxalic acid needed.
Step 1: Convert the given volume to liters:
150 ml = 150/1000 = 0.15 liters
Step 2: Rearrange the formula to solve for moles of solute:
mols of solute = M x volume of solution in liters
mols of solute = 0.442 M x 0.15 L
Step 3: Calculate the moles of the solute:
mols of solute = 0.0663 moles
Step 4: Look up the molar mass of oxalic acid (C2H2O4) in the periodic table or a reference source. The molar mass of C2H2O4 is 90.03 g/mol.
Step 5: Calculate the mass of oxalic acid needed using the following equation:
mass = moles × molar mass
mass = 0.0663 moles x 90.03 g/mol
Step 6: Calculate the mass of oxalic acid needed:
mass = 5.94 grams
Therefore, to prepare 150 ml of 0.442 M C2H2O4, you need approximately 5.94 grams of oxalic acid.