👉 The term "subcarbonaceous" is often used in chemistry and physics to describe a substance that contains only carbon atoms. It refers to substances with a high percentage of carbon by weight, typically between 98% and 99%. This means that they have no oxygen or nitrogen elements present, making them very light and dense. For example, a subcarbonaceous material might be made from materials like wood, which contains only carbon atoms. Another common example is graphite, which contains only carbon
