Question

The compound borazine consists of 40.29% boron, 7.51%

Answer 1

Answer:

$B_3H_6N_3$

Explanation:

Hello there!

In this case, since the mass percentages in a compound which is wanted to know the molecular formula, can be assumed to be the masses, we first need to compute the moles they have in the formula unit:

$n_B=40.29gB*\frac{1molB}{10.811gB} =3.73molB\\\\n_H=7.51gH*\frac{1molH}{1.01gH} =7.44molH\\\\n_N=52.20gN*\frac{1molN}{14.01gN} =3.73molN$

Next, we divide each moles by the fewest ones (3.73 mol) in order to find the subscript in the empirical formula first:

$B:\frac{3.73}{3.73}=1 \\\\H:\frac{7.44}{3.73}=2\\\\N:\frac{3.73}{3.73}=1$

Then, the empirical formula is BH2N whose molar mass is 26.83 g/mol, so the ratio of molecular to empirical is 80.50/26.83=3; therefore, the molecular formula is three times the empirical one:

$B_3H_6N_3$

Best regards!