If 4.36g of a hydrate of the salt baCl2 is heated and in the process losses 0.6431g of mass, show all your work to calculate the amount of water X in the hydrate, BaCl2.XH2O
To calculate the amount of water (X) in the hydrate BaCl2.XH2O, we need to determine the mass of water lost during the heating process. Here's how you can derive the answer:
1. Start by finding the mass of anhydrous BaCl2 (without water) that remains after heating. To do this, subtract the mass loss from the initial mass of the hydrate:
Mass of BaCl2 = Initial mass - Mass loss
= 4.36g - 0.6431g
= 3.7169g
2. Next, determine the molecular weight of BaCl2 by adding the atomic weights of each element:
Molecular weight of BaCl2 = Atomic weight of Ba + (2 x Atomic weight of Cl)
= 137.33 g/mol + (2 x 35.45 g/mol)
= 208.23 g/mol
3. Now, we need to calculate the number of moles of BaCl2. Divide the mass of BaCl2 by its molar mass:
Moles of BaCl2 = Mass of BaCl2 / Molecular weight of BaCl2
= 3.7169g / 208.23 g/mol
= 0.0178 mol
4. Since the formula of the hydrate is BaCl2.XH2O, every mole of BaCl2 will be associated with X moles of H2O. Hence, to find X, we compare the number of moles of BaCl2 to the number of moles of H2O lost. The molar ratio of BaCl2 to H2O is 1: X.
Moles of H2O lost = Moles of BaCl2
5. Finally, we can calculate the mass of water lost during heating by multiplying the moles of H2O lost by its molar mass:
Mass of H2O lost = Moles of H2O lost x Molar mass of H2O
The resulting value will represent the amount of water (XH2O) lost from the hydrate.
To calculate the amount of water (X) in the hydrate BaCl2.XH2O, we need to determine the mass of water lost during the heating process.
Given:
Mass of the hydrate before heating = 4.36g
Mass lost during heating = 0.6431g
Step 1: Calculate the mass of the anhydrous salt (BaCl2)
Mass of the anhydrous salt = Mass before heating - Mass lost during heating
Mass of the anhydrous salt = 4.36g - 0.6431g = 3.7169g
Step 2: Calculate the molar mass of BaCl2
The molar mass of BaCl2 = atomic mass of Ba + 2 * atomic mass of Cl
The atomic mass of Ba (barium) = 137.33 g/mol
The atomic mass of Cl (chlorine) = 35.45 g/mol
Molar mass of BaCl2 = 137.33 g/mol + 2 * 35.45 g/mol = 208.23 g/mol
Step 3: Calculate the number of moles of BaCl2
Number of moles of BaCl2 = Mass of BaCl2 / Molar mass of BaCl2
Number of moles of BaCl2 = 3.7169g / 208.23 g/mol
Step 4: Determine the ratio of moles between BaCl2 and H2O
From the chemical formula of BaCl2.XH2O, we can see that the ratio between BaCl2 and H2O is 1:1. This means that for every 1 mole of BaCl2, there is 1 mole of H2O.
Step 5: Calculate the number of moles of H2O
Number of moles of H2O = Number of moles of BaCl2
Step 6: Calculate the mass of H2O lost during heating
Mass of H2O lost = Number of moles of H2O * Molar mass of H2O
Note that the molar mass of H2O (water) is 18.02 g/mol.
Step 7: Calculate the mass of water X in the hydrate
Mass of water X = Mass lost during heating - Mass of H2O lost
Now let's calculate the values from Step 3 to 7:
Step 3:
Number of moles of BaCl2 = 3.7169g / 208.23 g/mol ≈ 0.0178 mol
Step 5:
Number of moles of H2O = Number of moles of BaCl2 = 0.0178 mol
Step 6:
Mass of H2O lost = Number of moles of H2O * Molar mass of H2O
Mass of H2O lost = 0.0178 mol * 18.02 g/mol ≈ 0.3204 g
Step 7:
Mass of water X = Mass lost during heating - Mass of H2O lost
Mass of water X = 0.6431 g - 0.3204 g ≈ 0.3227 g
Therefore, the amount of water (X) in the hydrate BaCl2.XH2O is approximately 0.3227 grams.