1.654 of a hydrated acid H2C2O4.xH2O was dissolved in water and the soultion was made up to 250cm3 . 23.80cm3 of this solution required 25.00cm3 of 0.100moldm-3 NaOH to reach the end point. Identify the value of x and the formula of the hydrated acid H2C2O4.xH2Or.

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The answer is 2

To identify the value of x and the formula of the hydrated acid H2C2O4.xH2O, we need to use the concept of stoichiometry and use the given information to determine the molar ratio and find the value of x.

Here's how you can calculate it step by step:

1. Calculate the number of moles of NaOH used:
Moles of NaOH = concentration (mol/dm³) × volume (dm³)
Moles of NaOH = 0.100 mol/dm³ × 0.02500 dm³ = 0.00250 mol

2. Based on the balanced chemical equation, determine the stoichiometric ratio between NaOH and H2C2O4:
NaOH + H2C2O4 → NaC2O4 + 2H2O
From the equation, we can see that 1 mole of NaOH reacts with 1 mole of H2C2O4.

3. Calculate the number of moles of H2C2O4:
Moles of H2C2O4 = 0.00250 mol

4. Calculate the initial number of moles of H2C2O4 in the 23.80 cm³ solution:
Moles of H2C2O4 = (Moles per cm³) × Volume (cm³)
Moles of H2C2O4 = (0.00250 mol) × (23.80 cm³ / 250.00 cm³)
Moles of H2C2O4 = 0.000238 mol

5. Determine the molar mass of H2C2O4:
Molar mass of H2C2O4 = (2 × molar mass of H) + (2 × molar mass of C) + (4 × molar mass of O)
Molar mass of H2C2O4 = (2 × 1.01 g/mol) + (2 × 12.01 g/mol) + (4 × 16.00 g/mol)
Molar mass of H2C2O4 = 90.04 g/mol

6. Calculate the mass of H2C2O4:
Mass of H2C2O4 = Moles of H2C2O4 × Molar mass of H2C2O4
Mass of H2C2O4 = 0.000238 mol × 90.04 g/mol
Mass of H2C2O4 = 0.0215 g

7. Determine the mass of water in H2C2O4.xH2O:
Mass of water = Mass of hydrated acid - Mass of anhydrous acid
Mass of water = 0.0215 g - (0.001654 × molar mass of H2C2O4)

8. Now, we need to find the value of x:
Mass of water = x × (molar mass of H2O)
x = (Mass of water) / (molar mass of H2O)
x = (Mass of water) / 18.02 g/mol

Perform the calculations to find the value of x.

After finding the value of x, the formula of the hydrated acid can be determined. It is H2C2O4.xH2O, where x represents the value determined in step 8.

Oxalic acid.xH2O +2NAOH ???????