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?

Answer 1

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.

Answer 2

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.

Answer 3

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.

Answer 4

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?

Answer 5

i multiplied 207 by 1.200 to get 248.4, was that the value that you meant by being close to 244?

Answer 6

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).