What mass of oxalic acid dihydrate , H2C2O4•2H2O, is required to prepare 220.0 ml of a 1.28 M solution of oxalic acid ?
How many mols do you need? That is M x L = 1.28M x 0.220L = ?
Then mol = g/molar mass. You know molar mass and you know mols, solve for grams.
M*L = 1.28M*0.220L = 0.282mols
molar mass = 126g
126g*0.282 = 35.5g
To determine the mass of oxalic acid dihydrate required, we can follow these steps:
Step 1: Find the molar mass of oxalic acid dihydrate:
The molar mass of H2C2O4 (oxalic acid) is:
2(1.008 g/mol for hydrogen) + 2(12.011 g/mol for carbon) + 4(16.00 g/mol for oxygen) = 90.034 g/mol.
Adding two water molecules (2H2O) to the formula, the molar mass becomes:
90.034 g/mol + 2(2(1.008 g/mol for hydrogen) + 16.00 g/mol for oxygen) = 126.064 g/mol.
Step 2: Calculate the moles of oxalic acid required:
The given concentration is 1.28 M (moles per liter) and the volume is 220.0 ml (0.220 L). Therefore, the moles of oxalic acid required can be calculated as:
moles = concentration x volume
moles = 1.28 M x 0.220 L = 0.2816 mol.
Step 3: Convert moles to grams:
To convert moles to grams, we multiply the number of moles by the molar mass of oxalic acid dihydrate:
mass = moles x molar mass
mass = 0.2816 mol x 126.064 g/mol = 35.51218 g.
Step 4: Round the result to an appropriate number of significant figures:
The mass of oxalic acid dihydrate required to prepare 220.0 ml of a 1.28 M solution is approximately 35.5 g.
To determine the mass of oxalic acid dihydrate required to prepare the given solution, we need to use the formula:
Molarity (M) = (moles of solute) / (volume of solution in liters)
Step 1: Convert the volume of the solution from milliliters (ml) to liters (L).
220.0 ml = 220.0 / 1000 = 0.220 L
Step 2: Determine the moles of solute (oxalic acid) using the formula:
Moles = Molarity × Volume (in liters)
Moles = 1.28 M × 0.220 L = 0.2816 moles
Step 3: Calculate the molar mass of oxalic acid dihydrate, H2C2O4•2H2O.
H (1 atom) + C (2 atoms) + O (4 atoms) + 2(H2O) = 2(1.00784 g/mol) + 12.0107 g/mol + 4(15.999 g/mol) + 2(2(1.00784 g/mol) + 15.999 g/mol)
= 90.034 g/mol
Step 4: Calculate the mass of oxalic acid dihydrate using the formula:
Mass (g) = Moles × Molar mass
Mass = 0.2816 moles × 90.034 g/mol
= 25.315 g
Therefore, 25.315 grams of oxalic acid dihydrate are required to prepare 220.0 ml of a 1.28 M solution of oxalic acid.