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
BaCl2*2H2O --> BaCl2 +2H20
4.36g ............... 3.72 ... 0.643g
Convert each of the mass of product to moles.
3.72 g BaCl2 x (1 mol BaCl2 / 208.3 g BaCl2) = 0.0179 mol BaCl2
0.643g H2O x (1 mol H2O / 18.0 g H2O) = 0.0357 mol H2O
Mole H2O / mole BaCl2 = 2 / 1
Hi
I am in university of calgary also in chemistry 201 also haha..
Anyways, i did the same thing as fat and got 2 also..so im guessing it is the right answer.
To calculate the amount of water (X) in the hydrate, BaCl2.XH2O, we need to use the concept of percent composition.
Step 1: Determine the mass of the anhydrous salt (BaCl2).
Since the hydrated salt loses 0.6431g of mass upon heating, the mass of the anhydrous salt (BaCl2) remaining is:
Mass of anhydrous salt = Initial mass - Mass loss during heating
= 4.36g - 0.6431g
= 3.7169g
Step 2: Calculate the mass of water lost.
The mass of water lost during the heating process is given by the mass loss:
Mass of water lost = Mass loss during heating
= 0.6431g
Step 3: Calculate the number of moles of the anhydrous salt (BaCl2).
To do this, we need the molar mass of BaCl2. The molar mass of BaCl2 is:
Molar mass of BaCl2 = (molar mass of Ba) + 2 * (molar mass of Cl)
= (137.33 g/mol) + 2 * (35.45 g/mol)
= 208.23 g/mol
Number of moles of BaCl2 = Mass of anhydrous salt / Molar mass of BaCl2
= 3.7169g / 208.23 g/mol
= 0.0178637 mol
Step 4: Determine the molar ratio between BaCl2 and H2O.
From the chemical formula of the hydrate, BaCl2.XH2O, we know that there is one mole of BaCl2 for every X moles of H2O. Therefore, the molar ratio of BaCl2 to H2O is 1:X.
Step 5: Calculate the number of moles of water (X).
By using the molar ratio, we can calculate the number of moles of water (X):
Number of moles of water (X) = X * Number of moles of BaCl2
Step 6: Calculate the mass of water (X).
Using the molar mass of water (H2O), which is 18.015 g/mol:
Mass of water (X) = Number of moles of water (X) * Molar mass of water
= X * 18.015 g/mol
Step 7: Equate the mass of water lost to the calculated mass of water (X).
Since the mass of water lost during heating is 0.6431g, we can set up the equation:
Mass of water lost = Mass of water (X)
0.6431g = X * 18.015 g/mol
Solving for X, we can rearrange the equation:
X = Mass of water lost / (Molar mass of water)
= 0.6431g / 18.015 g/mol
≈ 0.0357 mol
Therefore, the amount of water (X) in the hydrate, BaCl2.XH2O, is approximately 0.0357 mol.