Help me with this;
For the second part of the analysis,you will be provided with hydrated crystal of oxalic acid (H2C204. 2H2O). weigh out accurately about 1.575g of oxalic acid in a weighing bottle. Dissolve the acid in a beaker, then transfer the solution completely to 250cm3 standard volunteer flask and make up to the mark. shake it to ensure uniformity. Fill the burette with your prepared oxalic acid solution. Pipette 25cm3 of the given NaOH solution and titrate this against your oxalic acid solution using two or three drops of phenolphthalein,as indicator. Repeat the titration until consistent litres are obtained. From your result.calculate
(1) The concentration of the oxalic acid solution in moldm3
(2).The concentration of the oxalic acid solution in g/dm3
(3) The percentage purity of the sample of oxalic acid
Please ??
1.It would be nice to know what the first part was.
2. It would be nice to know the molarity of the NaOH. The problem can't be worked without it.
To calculate the concentration of the oxalic acid solution and the percentage purity of the sample, we first need to understand the process and perform the necessary calculations step by step:
Step 1: Calculation of the Concentration of the Oxalic Acid Solution in mol/dm³
1. Convert the mass of the oxalic acid weighed (1.575g) to moles.
- To do this, we need to know the molar mass of oxalic acid (H₂C₂O₄).
- The molar mass of H₂C₂O₄ = (2 x molar mass of H) + (2 x molar mass of C) + (4 x molar mass of O)
- The molar mass of H₂C₂O₄ = (2 x 1.01) + (2 x 12.01) + (4 x 16.00) = 90.03 g/mol
- The number of moles of oxalic acid = mass / molar mass
- Moles of oxalic acid = 1.575g / 90.03g/mol = 0.0175 mol
2. Calculate the volume of oxalic acid solution used in the titration.
- The volume of solution used is given as 25 cm³.
3. Calculate the concentration of the oxalic acid solution.
- Concentration (C) = Moles / Volume
- Concentration = 0.0175 mol / 0.025 dm³ = 0.7 M (mol/dm³)
Therefore, the concentration of the oxalic acid solution is 0.7 moldm³.
Step 2: Calculation of the Concentration of the Oxalic Acid Solution in g/dm³
1. Calculate the molar mass of H2C2O4·2H2O (oxalic acid hydrated crystal).
- For this calculation, we consider the molar mass of the hydrated crystal.
- The molar mass of H2C2O4·2H2O = [(2 x 1.01) + (2 x 12.01) + (4 x 16.00)] + [(2 x (2 x 1.01) + 16.00)] = 126.07 g/mol
2. Calculate the concentration of the oxalic acid solution in g/dm³.
- Concentration (C) = Moles x Molar mass
- Concentration = 0.0175 mol x 126.07 g/mol / 0.025 dm³ = 88.84 g/dm³
Therefore, the concentration of the oxalic acid solution is 88.84 g/dm³.
Step 3: Calculation of the Percentage Purity of the Sample of Oxalic Acid
1. Assume the purity of the oxalic acid sample as "x."
2. Calculate the number of moles of the pure oxalic acid.
- Moles of pure oxalic acid = Concentration x Volume in dm³
- Moles of pure oxalic acid = 0.7 M x 0.025 dm³ = 0.0175 mol
3. Calculate the mass of the pure oxalic acid in the sample.
- Mass of pure oxalic acid = Moles x Molar mass
- Mass of pure oxalic acid = 0.0175 mol x 90.03 g/mol = 1.57 g
4. Calculate the percentage purity.
- Percentage purity = (Mass of pure oxalic acid / Mass of the sample) x 100
- Percentage purity = (1.57 g / 1.575 g) x 100 = 99.68%
Therefore, the percentage purity of the sample of oxalic acid is approximately 99.68%.