Why did Justus von Liebig burn organic compounds with copper oxide?

Justus von Liebig burned organic compounds with copper oxide to improve the method of organic analysis. By oxidizing these compounds, he could identify the resulting products—specifically water vapor and carbon dioxide—and determine their mass by weighing them after absorption.1

This procedure, perfected in 1831, allowed for the carbon content of organic compounds to be measured with significantly greater precision than previous techniques. Furthermore, Liebig’s method was faster and simpler, enabling chemists to perform multiple analyses in a single day. This technical breakthrough was a key factor in the rapid progress of organic chemistry during the 1830s and the subsequent emergence of biochemistry and clinical chemistry. Cupric oxide is specifically utilized for this purpose because it effectively oxidizes carbon compounds.123