If you start with 1.200 g of BaCl2 X(multiplied) 2H20 and heat if for 4-8 min, what will be the mass of the water removed?
No. The molar mass of BaCl2.2H2O is
Ba = 137.327
Cl = 35.453 x 2 = 70.9054
H2O = 18.015 x 2 = 36.0306
total = 244.263 for BaCl2.2H2O.
1.2/244.263 = 0.00491 moles BaCl2.2H2O
moles H2O evolved = 0.00491 x (2 moles H2O/1 mole BaCl2.2H2O) = 0.00491 x 2 = 0.00983 moles H2O.
grams H2O = moles x molar mass = 0.00983 x 18.015 = 0.17701 grams which I would round to 0.18 grams (to two significant figures since 1.2 has two).
Moles BaCl2.2H2O = grams/molar mass
moles BaCl2.2H2O x (2 moles H2O/1 mole BaCl2.2H2O) = moles BaCl2.2H2O x 2/1 = ??
mass H2O = moles H2O x molar mass H2O
Post your work if you get stuck.
so would i take the mass of BaCl2 which is 207 and then divide it by the molar mass of 1.200 to get 172? I'm not sure that it's right.
No. You want the molar mass of BaCl2.2H2O since that's the material that has a mass of 1.2 grams. I think its 244 something.
so i found the molar mass of BaCl2.2H20 to be to be 207. but when i divided that by 1.200 i got 172.5. how did you get the value 244?
i multiplied 207 by 1.200 to get 248.4, was that the value that you meant by being close to 244?
To find the mass of water removed, we need to determine the amount of water present in the compound and then calculate the difference in mass before and after heating.
The compound BaCl2*2H2O consists of barium chloride (BaCl2) and water (H2O). The number 2 in BaCl2*2H2O indicates that there are two water molecules present for each barium chloride molecule. Therefore, the molar ratio of BaCl2 to H2O is 1:2.
First, we need to calculate the molar mass of BaCl2*2H2O:
Molar mass of Ba = 137.33 g/mol
Molar mass of Cl2 = 70.90 g/mol
Molar mass of H2 = 2.02 g/mol
Molar mass of O = 16.00 g/mol
So, molar mass of BaCl2 = (137.33 + 70.90) g/mol = 208.23 g/mol
molar mass of 2H2O = (2 * 2.02 + 16.00) g/mol = 36.04 g/mol
The total molar mass of BaCl2*(2H2O) = 208.23 + 36.04 = 244.27 g/mol
Next, we calculate the moles of BaCl2*(2H2O) we have:
moles = mass / molar mass
Given mass of BaCl2*(2H2O) = 1.200 g
moles of BaCl2*(2H2O) = 1.200 g / 244.27 g/mol
Since the molar ratio of water to BaCl2 is 2:1, we know that the moles of water is twice the moles of BaCl2*(2H2O).
moles of H2O = 2 * (1.200 g / 244.27 g/mol)
Now, we can calculate the mass of water present:
mass of H2O = moles of H2O * molar mass of H2O
Finally, to find the mass of water removed, we subtract the mass of water present before heating from the mass of water present after heating.
Please provide the time for heating between 4-8 minutes in order to calculate the mass of water removed.