with the use of calculations explain how would you prepare a 250ml of 0,2dm³ concentration solution of oxalic acid
a. figur out the mass of oxalic acid needed:
mass= .25*molmassOxalic acid
b. add that to 250 ml water, stir, and label.
To calculate the mass of oxalic acid needed to prepare a 250 ml solution with a concentration of 0.2 mol/dm³ (0.2 M), you would follow these steps:
Step 1: Understand the given information:
- Concentration requirement: 0.2 mol/dm³
- Volume required: 250 ml = 0.25 dm³
Step 2: Use the formula for concentration:
Concentration (M) = moles (mol) / volume (dm³)
Step 3: Rearrange the formula to solve for moles:
moles (mol) = concentration (M) x volume (dm³)
Step 4: Substitute the known values:
moles (mol) = 0.2 mol/dm³ x 0.25 dm³
Step 5: Calculate the moles
moles (mol) = 0.05 mol
Step 6: Determine the molar mass of oxalic acid:
The molar mass of oxalic acid (H₂C₂O₄) can be calculated as follows:
- Atomic mass of hydrogen (H) = 1 g/mol
- Atomic mass of carbon (C) = 12 g/mol
- Atomic mass of oxygen (O) = 16 g/mol
Molar mass of H₂C₂O₄ = 2(1 g/mol) + 2(12 g/mol) + 4(16 g/mol) = 90 g/mol
Step 7: Calculate the mass of oxalic acid (g):
mass (g) = moles (mol) x molar mass (g/mol)
mass (g) = 0.05 mol x 90 g/mol
Step 8: Calculate the mass:
mass (g) = 4.5 g
Therefore, to prepare a 250 ml solution with a concentration of 0.2 M, you will need 4.5 g of oxalic acid.
To prepare a 250ml solution with a concentration of 0.2dm³, we need to use calculations involving the molecular weight of oxalic acid, known as H2C2O4.
Here's how you can calculate the required amount of oxalic acid:
Step 1: Determine the molecular weight of oxalic acid.
The molecular weight of oxalic acid (H2C2O4) can be calculated by adding up the atomic weights of its constituent atoms:
H: 1 g/mol (2 atoms)
C: 12 g/mol (2 atoms)
O: 16 g/mol (4 atoms)
Molecular weight of H2C2O4 = 2(1) + 2(12) + 4(16) = 90 g/mol
Step 2: Calculate the number of moles of oxalic acid needed.
The concentration of the solution is given as 0.2dm³. Since 1 dm³ is equal to 1000 ml, 0.2 dm³ is equal to 200 ml. Therefore, we need to prepare a solution using 200 ml of a 0.2 M (mol/dm³) solution of oxalic acid.
To calculate the number of moles, multiply the concentration (0.2 mol/dm³) by the volume in dm³ (0.2dm³):
Number of moles = 0.2 mol/dm³ * 0.2 dm³ = 0.04 moles
Step 3: Calculate the mass of oxalic acid needed.
Using the number of moles calculated in the previous step and the molecular weight of oxalic acid, we can calculate the mass needed using the following formula:
Mass (g) = Number of moles * Molecular weight
Mass (g) = 0.04 moles * 90 g/mol = 3.6 grams
Therefore, to prepare a 250 ml solution with a concentration of 0.2dm³, you would need to dissolve 3.6 grams of oxalic acid in distilled water and then adjust the final volume to 250 ml.