Question

A. How many grams of AlCl3 (MW=133) will be produced ?

B. An analysis of a hydrocarbon revealed that it contained 7.8% hydrogen and 92.2% carbon by weight. A mass Spectra revealed that its molecular weight was 78 amu. What is the empirical formula and what is the molecular formula?

Answer 1

We need full question to answer A

Question B

Let us take 100 gm of compound

Mass of carbon = 92.2 gm

Moles of carbon = 92.2 gm / 12 gm /mol = 7.683 Mole

Mass of hydrogen = 7.8 gm

Moles of hydrogen = 7.8 gm / 1.008 gm /mol = 7.73 Mole

Molar ratio of carbon and Hydrogen and oxygen = 7.683 : 7.73 = 1 : 1

Empirical formula = CH

Molecular formula = C₆H₆