Answer:
The molecular formula of the compound is B₂H₆
Step-by-step explanation:
From the question given above, the following data were obtained:
Composition of Boron (B) = 78.14%
Composition of Hydrogen (H) = 21.86%
Molar mass of compound = 27.67 g/mol
Molecular formula =?
Next, we shall determine the empirical formula of the compound. This can be obtained as follow:
B = 78.14%
H = 21.86%
Divide by their molar mass
B = 78.14 / 11 = 7.104
H = 21.86 / 1 = 21.86
Divide by the smallest
B = 7.104 / 7.104 = 1
H = 21.86 / 7.104 = 3
Thus, the empirical formula of the compound is BH₃
Finally, we shall determine the molecular formula of the compound. This can be obtained as illustrated below:
Molecular formula = empirical formula × n
Molecular formula = [BH₃]ₙ
Thus, we shall determine the value of n to obtain the molecular formula. The value of n can be obtained as follow:
[BH₃]ₙ = 27.67
[11 + (3×1)]n = 27.67
[11 + 3]n = 27.67
14n = 27.67
Divide both side by 14
n = 27.67 / 14
n = 2
Molecular formula = [BH₃]ₙ
Molecular formula = [BH₃]₂
Molecular formula = B₂H₆