Question

An organic compound containing carbon, hydrogen and oxygen is found to have 40% Carbon,

6.66% Hydrogen and 53.34% oxygen. If molecular mass is 120. Find molecular formula.​

Answer 1

Given :-

• Carbon = 40 %

• Hydrogen = 6.66  %

• Oxygen = 53.34 %

Solution :-

Relative no of atoms

• First we need to divide the % composition of the elements with the atomic mass

Carbon

C = 40 / 12 = 3.33

Hydrogen

H = 6.66 / 1 = 6.66

Oxygen

O = 53.34 / 16 = 3.33

Simple ratio

• Divide all the values obtained above with the least no obtained ( i.e. 3.33 ) in this case

Carbon

C  = 3.33 / 3.33 = 1

Hydrogen

H = 6.66 / 3.33  = 2

Oxygen

O = 3.33 / 3.33 = 1

⟹ Empirical formula = CH2O

⟹ Empirical mass = C + 2 (H) + O

⟹ Empirical mass = 12 + 2 (1) + 16

⟹ Empirical mass = 12 + 2 + 16

⟹ Empirical mass = 30g

Molecular mass = n x Empirical mass

⟹ n = Molecular mass /  Empirical mass

⟹ n = 120 / 30

⟹ n = 4

Similarly ,

⟹ Molecular formula = n x Empirical formula

⟹ Molecular formula = 4 ( CH2O )

∴ Molecular formula = C 4 H 8 O 4

Answer 2

Answer:

the answer is posted....see it.....