Question

An unknown compound contains only C, H, and O. Combustion of 6.10 g of this compound produced 14.9 g of CO₂ and 6.10 g of H₂O. What is the empirical formula of the unknown compound?

Answer 1

The answer to your question is C₃H₃O

Step-by-step explanation:

Data

Combustion of a compound C, H, O

mass = 6.10 g

mass CO2 = 14.9 g

mass of water = 6.10 g

Reaction

Cx Hy Oz + O2 ⇒ CO2 + H2O

Process

1.- Calculate the moles of carbon

44 g of CO2 -------------- 12 g of carbon

14.9 g of CO2 ------------- x

x = (14.9 x 12) / 44

x = 4.06 g

12 g of C ------------------ 1 mol

4.06 g ------------------- x

x = (4.06 x 1) / 12

x = 0.34 moles

2.- Calculate the moles of hydrogen

18 g of water ------------- 1 g of hydrogen

6.10 g of water ---------- x

x = (6.10 x 1) / 18

x = 0.33 g

1 g of H ---------------- 1 mol of H

0.33 g ---------------- x

x = (0.33 x 1) / 1

x = 0.33 moles of H

3.- Calculate the mass of oxygen

mass of Oxygen = 6.10 - 4.06 - 0.33

= 1.71 g

16 g of O --------------- 1 mol of O

1.71 g of O ------------- x

x = (1.71 x 1) / 16

x = 0.11 moles

4.- Divide by the lowest number of moles

Carbon = 0.34 / 0.11 = 3

Hydrogen = 0.33 / 0.11 = 3

Oxygen = 0.11 /0.11 = 1

5.- Write the empirical formula

C₃H₃O