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2007-12-12 01:24:27 · 3 answers · asked by Shayna M 1 in Science & Mathematics ➔ Chemistry
Ba MW = 137.327 g/mole
Cl MW = 35.453 g/mole
H MW = 1.0079 g/mole
O MW = 15.9994 g/mole
BaCl2•2H2O MW = 137.327 + 2(35.453) + 4(1.0079) + 2(15.9994) =
= 244.2634 g/mole
H2O MW = 2(1.0079) + 15.9994 = 18.0152 g/mole
% H2O in BaCl2•2H2O = weight water in BaCl2•2H2O/ weight BaCl2•2H2O * 100
= 2*18.0152/244.2634 * 100 = 14.75%
2007-12-12 01:34:34 · answer #1 · answered by Dr Dave P 7 · 1⤊ 0⤋
Molar mass of BaCl2*2H2O = 137.3 + 35.5 x 2 +2 x 18 = 244.3 g/mol
Molar mass of water in the formula = 2 x 18 = 36 g/mol
36/244.3 = 14.7%
2007-12-12 01:29:38 · answer #2 · answered by lhvinny 7 · 0⤊ 0⤋
Divide the mass of two water molecules (36 g) by the molar mass of the whole compound including the two water molecules. Convert that to a percentage (multiply by 100) and you've got the answer.
2007-12-12 01:30:30 · answer #3 · answered by hcbiochem 7 · 0⤊ 0⤋