Question

An unknown compound contains only C , H , and O . Combustion of 5.60 g of this compound produced 13.7 g CO2 and 5.60 g H2O . What is the empirical formula of the unknown compound?

Answer 1

Answer:

Empirical formula of compound  is C₄H₈O

Explanation:

Given data:

Mass of compound = 5.60 g

Mass of CO₂ = 13.7 g

Mass of H₂O = 5.60 g

Empirical formula of compound = ?

Solution:

Percentage of C:

13.7 g/5.60 g × 12/44× 100

2.45×0.273× 100 = 66.9%

Percentage of H:

5.60 g/ 5.60 g × 2.016/18 × 100

11.2%

Percentage of O:

(66.9% + 11.2%) - 100 = 21.9%

Grams atom of  C , H, O

66.9/12 = 5.6

11.2 / 1.008 = 11.11

21.9 / 16 = 1.4

Atomic ratio:

           C                 :               H           :              O

           5.6/1.4         :            11.11/1.4    :            1.4/1.4

              4                :               8            :               1

Empirical formula:

C₄H₈O