Why more carbon dioxide is produced while burning wood than the weight of the wood?

Goal or Problem

While burning wood, the weight of carbon dioxide produced during combustion is greater than the weight of the burned wood. More specifically, while burning 1 kilogram of wood, approximately 1.8 kilogram of carbon dioxide is produced. How is this possible?

Idea

Combustion of wood is a chemical reaction among molecules of wood and oxygen molecules in the air. The result of the reaction is mainly water and carbon dioxide. The ratio of other products of wood combustion, such as ash and other gasses is negligible.

More specifically, burning of 1 kilogram of wood requires 1.42 kilograms of oxygen. The outcome is 1.83 kilogram of carbon dioxide and 0.59 kilogram of water. In reality, the amounts vary slightly based on wood species and humidity of wood.

References

Combustion Principles